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Find video protocols related to scientific articles indexed in Pubmed.
A nanoscale study of charge extraction in organic solar cells: the impact of interfacial molecular configurations.
Nanoscale
PUBLISHED: 10-18-2014
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In the optimization of organic solar cells (OSCs), a key problem lies in the maximization of charge carriers from the active layer to the electrodes. Hence, this study focused on the interfacial molecular configurations in efficient OSC charge extraction by theoretical investigations and experiments, including small molecule-based bilayer-heterojunction (sm-BLHJ) and polymer-based bulk-heterojunction (p-BHJ) OSCs. We first examined a well-defined sm-BLHJ model system of OSC composed of p-type pentacene, an n-type perylene derivative, and a nanogroove-structured poly(3,4-ethylenedioxythiophene) (NS-PEDOT) hole extraction layer. The OSC with NS-PEDOT shows a 230% increment in the short circuit current density compared with that of the conventional planar PEDOT layer. Our theoretical calculations indicated that small variations in the microscopic intermolecular interaction among these interfacial configurations could induce significant differences in charge extraction efficiency. Experimentally, different interfacial configurations were generated between the photo-active layer and the nanostructured charge extraction layer with periodic nanogroove structures. In addition to pentacene, poly(3-hexylthiophene), the most commonly used electron-donor material system in p-BHJ OSCs was also explored in terms of its possible use as a photo-active layer. Local conductive atomic force microscopy was used to measure the nanoscale charge extraction efficiency at different locations within the nanogroove, thus highlighting the importance of interfacial molecular configurations in efficient charge extraction. This study enriches understanding regarding the optimization of the photovoltaic properties of several types of OSCs by conducting appropriate interfacial engineering based on organic/polymer molecular orientations. The ultimate power conversion efficiency beyond at least 15% is highly expected when the best state-of-the-art p-BHJ OSCs are combined with present arguments.
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Effects of medium components and culture conditions on mycelial biomass and the production of bioactive ingredients in submerged culture of Xylaria nigripes (Ascomycetes), a Chinese medicinal fungus.
Int J Med Mushrooms
PUBLISHED: 10-02-2014
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The optimal culture conditions were investigated to maximize the production of mycelial biomass and bioactive ingredients in submerged cultivation of Xylaria nigripes, a Chinese medicinal fungus. The one-factor-at-a-time method was used to explore the effects of medium components, including carbon, nitrogen, mineral sources, and initial pH of the medium and environmental factors, such as culture temperature and rotation speed, on mycelial growth and production of bioactive ingredients. The results indicated that the optimal culture temperature and rotation speed were 25°C and 100 rpm in a medium with 20 g fructose, 6 g yeast extract, and 2 g magnesiun sulfate heptahydrate as carbon, nitrogen, and mineral sources, respectively, in 1 L distilled water with an initial medium pH of 5.5. With optimal medium components and conditions of cultivation, the maximal production of mycelial biomass was 6.64 ± 0.88 g/L, with maximal production of bioactive ingredients such as extracellular polysaccharides (2.36 ± 0.18 mg/mL), intracellular polysaccharides (2.38 ± 0.07 mg/g), adenosine (43.27 ± 2.37 mg/g), total polyphenols (36.57 ± 1.36 mg/g), and triterpenoids (31.29 ± 1.17 mg/g) in a shake flask culture. These results suggest that different bioactive ingredients including intracellular polysaccharides, adenosine, total polyphenols and triterpenoids in mycelia and extracellular polysaccharides in broth can be obtained from one simple medium for submerged cultivation of X. nigripes.
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Bioabsorbable fish scale for the internal fixation of fracture: a preliminary study.
Tissue Eng Part A
PUBLISHED: 09-12-2014
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Fish scales, which consist of type I collagen and hydroxyapatite (HA), were used to fabricate a bioabsorbable bone pin in this study. Fresh fish scales were decellularized and characterized to provide higher biocompatibility. The mechanical properties of fish scales were tested, and the microstructure of an acellular fish scale was examined. The growth curve of a myoblastic cell line (C2C12), which was cultured on the acellular fish scales, implied biocompatibility in vitro, and the morphology of the cells cultured on the scales was observed using scanning electron microscopy (SEM). A bone pin made of decellularized fish scales was used for the internal fixation of femur fractures in New Zealand rabbits. Periodic X-ray evaluations were obtained, and histologic examinations were performed postoperatively. The present results show good cell growth on decellularized fish scales, implying great biocompatibility in vitro. Using SEM, the cell morphology revealed great adhesion on a native, layered collagen structure. The Young's modulus was 332 ± 50.4?MPa and the tensile strength was 34.4 ± 6.9?MPa for the decellularized fish scales. Animal studies revealed that a fish-scale-derived bone pin improved the healing of bone fractures and degraded with time. After an 8-week implantation, the bone pin integrated with the adjacent tissue, and new extracellular matrix was synthesized around the implant. Our results proved that fish-scale-derived bone pins are a promising implant material for bone healing and clinical applications.
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Colchicine suppresses atrial fibrillation in failing heart.
Int. J. Cardiol.
PUBLISHED: 08-17-2014
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This study aimed to investigate the mechanism by which colchicine suppresses atrial fibrillation (AF) in a rabbit heart failure (HF) model.
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Sleep disorders increase the risk of burning mouth syndrome: a retrospective population-based cohort study.
Sleep Med.
PUBLISHED: 07-23-2014
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Sleep disorders (SD), including apnea and nonapnea, and burning mouth syndrome (BMS) have been mutually associated with systemic diseases. Based on our research, the association between BMS and SD has not been elucidated. We determined whether SD patients have an increased risk of BMS.
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Incidence and risk of atrial fibrillation in sleep-disordered breathing without coexistent systemic disease.
Circ. J.
PUBLISHED: 07-23-2014
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Although the link between sleep-disordered breathing (SDB) and atrial fibrillation (AF) has been reported, a population-based longitudinal cohort study was lacking. The goal of the present study was to investigate the AF risk carried by SDB, using the National Health Insurance Research Database in Taiwan. METHODS?AND?RESULTS: From 2000 to 2001, a total of 579,521 patients who had no history of cardiac arrhythmias or significant comorbidities were identified. Among them, 4,082 subjects with the diagnosis of SDB were selected as the study group, and the remaining 575,439 subjects constituted the control group. The study endpoint was the occurrence of new-onset AF. During a follow-up of 9.2±2.0 years, there were 4,023 patients (0.7%) experiencing new-onset AF. The occurrence rate of AF was higher in patients with SDB compared to those without it (1.3% vs. 0.7%, P<0.001). The AF incidences were 1.38 and 0.76 per 1,000 person-years for patients with and without SDB, respectively. After anadjustment for age and sex, SDB was a significant risk factor of AF with a hazard ratio of 1.536. The AF risk increased with increasing clinical severity of SDB, represented by the requirement of continuous positive airway pressure use.
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Increased risk of stroke in patients with chronic kidney disease after recurrent hypoglycemia.
Neurology
PUBLISHED: 07-16-2014
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In this study, we aimed to investigate the effect of hypoglycemia on cardiovascular outcomes in a sample of patients with chronic kidney disease (CKD).
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Shift of Exit Site During Ablation of Ventricular Tachycardia Originating from the Vicinity of Left Ventricular Summit.
J. Cardiovasc. Electrophysiol.
PUBLISHED: 06-20-2014
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A 44-year-old man with structurally normal heart underwent catheter ablation of left ventricular summit tachycardia. The initial mapping revealed the origin of tachycardia at the junction of great cardiac vein and anterior interventricular vein. During ablation the exit site shifted to the nearby regions, which was recognized by subtle changes of 12-lead ECG. Mapping and ablating at different exit sites rendered the tachycardia noninducible.
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Neonatal jaundice and increased risk of attention-deficit hyperactivity disorder: a population-based cohort study.
J Child Psychol Psychiatry
PUBLISHED: 06-19-2014
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Previous studies have posited conflicting results regarding the relationship between neonatal jaundice and the subsequent risk of attention-deficit hyperactivity disorder (ADHD). We therefore performed a large population study with a defined neonatal jaundice cohort to investigate the incidence and risk of physician-diagnosed ADHD in Taiwan.
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Conformational Flexibility in the Binding Surface of the Potassium Channel Blocker ShK.
Chembiochem
PUBLISHED: 06-08-2014
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ShK is a 35-residue peptide that binds with high affinity to human voltage-gated potassium channels through a conserved K-Y dyad. Here we have employed NMR measurements of backbone-amide (15) N spin-relaxation rates to investigate motions of the ShK backbone. Although ShK is rigid on the ps to ns timescale, increased linewidths observed for 11 backbone-amide (15) N resonances identify chemical or conformational exchange contributions to the spin relaxation. Relaxation dispersion profiles indicate that exchange between major and minor conformers occurs on the sub-millisecond timescale. Affected residues are mostly clustered around the central helix-kink-helix structure and the critical K22-Y23 motif. We suggest that the less structured minor conformer increases the exposure of Y23, known to contribute to binding affinity and selectivity, thereby facilitating its interaction with potassium channels. These findings have potential implications for the design of new channel blockers based on ShK.
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Kv1.3 channel-blocking immunomodulatory peptides from parasitic worms: implications for autoimmune diseases.
FASEB J.
PUBLISHED: 06-04-2014
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The voltage-gated potassium (Kv) 1.3 channel is widely regarded as a therapeutic target for immunomodulation in autoimmune diseases. ShK-186, a selective inhibitor of Kv1.3 channels, ameliorates autoimmune diseases in rodent models, and human phase 1 trials of this agent in healthy volunteers have been completed. In this study, we identified and characterized a large family of Stichodactyla helianthus toxin (ShK)-related peptides in parasitic worms. Based on phylogenetic analysis, 2 worm peptides were selected for study: AcK1, a 51-residue peptide expressed in the anterior secretory glands of the dog-infecting hookworm Ancylostoma caninum and the human-infecting hookworm Ancylostoma ceylanicum, and BmK1, the C-terminal domain of a metalloprotease from the filarial worm Brugia malayi. These peptides in solution adopt helical structures closely resembling that of ShK. At doses in the nanomolar-micromolar range, they block native Kv1.3 in human T cells and cloned Kv1.3 stably expressed in L929 mouse fibroblasts. They preferentially suppress the proliferation of rat CCR7(-) effector memory T cells without affecting naive and central memory subsets and inhibit the delayed-type hypersensitivity (DTH) response caused by skin-homing effector memory T cells in rats. Further, they suppress IFN? production by human T lymphocytes. ShK-related peptides in parasitic worms may contribute to the potential beneficial effects of probiotic parasitic worm therapy in human autoimmune diseases.-Chhabra, S., Chang, S. C., Nguyen, H. M., Huq, R., Tanner, M. R., Londono, L. M., Estrada, R., Dhawan, V., Chauhan, S., Upadhyay, S. K., Gindin, M., Hotez, P. J., Valenzuela, J. G., Mohanty, B., Swarbrick, J. D., Wulff, H., Iadonato, S. P., Gutman, G. A., Beeton, C., Pennington, M. W., Norton, R. S., Chandy, K. G. Kv1.3 channel-blocking immunomodulatory peptides from parasitic worms: implications for autoimmune diseases.
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Unipolar Peak-Negative Voltage as an Endocardial Electrographic Characteristic to Predict Overlying Abnormal Epicardial Substrates in Patients with Right Epicardial Ventricular Tachycardia.
J. Cardiovasc. Electrophysiol.
PUBLISHED: 06-03-2014
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The characteristics of endocardial electrograms needed to detect the overlying abnormal epicardial substrates in arrhythmogenic right ventricular cardiomyopathy with epicardial ventricular tachycardia (VT) remain unclear. This study investigated which of the endocardial electrogram characteristics could predict the overlying abnormal epicardial substrates.
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Relation of arterial stiffness assessed by brachial-ankle pulse wave velocity to complexity of coronary artery disease.
Am. J. Med. Sci.
PUBLISHED: 05-22-2014
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The progression of atherosclerosis leads to increased arterial stiffness. The present study used brachial-ankle pulse wave velocity (baPWV) to evaluate the connection between arterial stiffness in patients with chest pain and the presence and extent of coronary artery disease (CAD).
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Using the CHA2DS2-VASc Score for Refining Stroke Risk Stratification in 'Low-Risk' Asian Patients With Atrial Fibrillation.
J. Am. Coll. Cardiol.
PUBLISHED: 05-13-2014
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A new scoring system, the anticoagulation and risk factors in atrial fibrillation (ATRIA) score, was proposed for risk stratification in patients with atrial fibrillation (AF). Whether the ATRIA scheme can adequately identify patients who are at low risk of ischemic stroke remains unknown.
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Acute myocardial infarction in patients with atrial fibrillation with a CHA2DS2-VASc score of 0 or 1: A nationwide cohort study.
Heart Rhythm
PUBLISHED: 04-28-2014
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The risk of acute myocardial infarction (AMI) in patients with atrial fibrillation (AF) with a CHA2DS2-VASc score of 0 (for men) or 1 (for women) has not been previously investigated.
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Effect of different temperatures on the expression of the newly characterized heat shock protein 90 (Hsp90) in L3 of Anisakis spp. isolated from Scomber australasicus.
Vet. Parasitol.
PUBLISHED: 04-21-2014
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Anisakid nematodes are distributed worldwide in a wide variety of marine fishes and they are known to cause the zoonotic disease, anisakiasis. The temperature control is commonly applied for prevention and control of anisakiasis. To analyze the cellular response to temperature stress in Anisakis, the heat shock protein 90 (Hsp90) was chosen in the present study, as it plays a key role in many cellular processes and responds to stress conditions such as heat or cold shock. Anisakids were sampled from spotted mackerel Scomber australasicus caught from the coastal waters of Yilan, in northeastern Taiwan (25°N, 121°E). Anisakid nematodes were pre-identified morphologically and later molecularly by PCR-RFLP. In total, we obtained six species of the genus Anisakis, A. typica, A. pegreffii, A. paggiae, A. brevispiculata, A. physeteris, and a recombinant genotype between A. pegreffii and A. simplex sensu stricto. Thereby we provide new host and locality records for A. paggiae, A. brevispiculata and A. physeteris. The Hsp90 genes of five species (except the recombinant genotype) were cloned by rapid amplification of cDNA ends (RACE) and their deduced amino acid sequences were further characterized. Quantitative real-time PCR and Western blot analysis were used to examine the expression levels of the Hsp90 in A. pegreffii under different temperature conditions. Quantitative RT-PCR showed that Hsp90 transcript levels increased slightly under heat shock (50°C) treatment, and increased gradually during the first 3h, and thereafter, returned to its baseline value at 37°C. Under cold shock (4°C) treatment, the mRNA expression of Hsp90 did not change significantly. In addition, we found a clear time-dependent Hsp90 protein expression pattern of A. pegreffii exposed to high temperature. Our results suggest that the mRNA and protein expression patterns of Hsp90 are related to the temperature, and are especially significantly increased under heat stress.
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Microvascular permeability changes might explain cardiac tamponade after alcohol septal ablation for hypertrophic cardiomyopathy.
Tex Heart Inst J
PUBLISHED: 04-01-2014
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Various sequelae of alcohol septal ablation for hypertrophic obstructive cardiomyopathy have been reported. Of note, some cases of cardiac tamponade after alcohol septal ablation cannot be well explained. We describe the case of a 78-year-old woman with hypertrophic obstructive cardiomyopathy in whom cardiac tamponade developed one hour after alcohol septal ablation, probably unrelated to mechanical trauma. At that time, we noted a substantial difference in the red blood cell-to-white blood cell ratio between the pericardial effusion (1,957.4) and the peripheral blood (728.3). In addition to presenting the patient's case, we speculate that a possible mechanism for acute tamponade--alcohol-induced changes in microvascular permeability--is a reasonable explanation for cases of alcohol septal ablation that are complicated by otherwise-unexplainable massive pericardial effusions.
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Different characteristics and electrophysiological properties between early and late recurrences after acute successful catheter ablation of idiopathic right ventricular outflow tract arrhythmias during long-term follow-up.
Heart Rhythm
PUBLISHED: 03-30-2014
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Radiofrequency catheter ablation (RFCA) is an effective therapeutic strategy in eliminating drug-refractory idiopathic right ventricular outflow tract ventricular arrhythmias (RVOT VAs). It remains unclear what factors affect early and late VA recurrences after ablation.
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Incidence and prediction of ischemic stroke among atrial fibrillation patients with end-stage renal disease requiring dialysis.
Heart Rhythm
PUBLISHED: 03-24-2014
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Renal dysfunction is a significant risk factor for ischemic stroke in atrial fibrillation (AF). However, the incidence of ischemic stroke and how to predict its occurrence among AF patients with end-stage renal disease (ESRD) are unclear.
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Sleep disorders increase the risk of osteoporosis: a nationwide population-based cohort study.
Sleep Med.
PUBLISHED: 03-22-2014
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This study evaluated the relationship between sleep disorders (SDs) and osteoporosis risk in Taiwan.
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Acupoint-specific, frequency-dependent, and improved insulin sensitivity hypoglycemic effect of electroacupuncture applied to drug-combined therapy studied by a randomized control clinical trial.
Evid Based Complement Alternat Med
PUBLISHED: 03-22-2014
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The application of electroacupuncture (EA) to specific acupoints can induce a hypoglycemic effect in streptozotocin-induced rats, normal rats, and rats with steroid-induced insulin resistance. EA combined with the oral insulin sensitizer rosiglitazone improved insulin sensitivity in rats and humans with type II diabetes mellitus (DM). There are different hypoglycemic mechanisms between Zhongwan and Zusanli acupoints by EA stimulation. On low-frequency (2?Hz) stimulation at bilateral Zusanli acupoints, serotonin was involved in the hypoglycemic effect in normal rats. Moreover, after 15?Hz EA stimulation at the bilateral Zusanli acupoints, although enhanced insulin activity mainly acts on the insulin-sensitive target organs, the muscles must be considered. In addition, 15?Hz EA stimulation at the bilateral Zusanli acupoints has the combined effect of enhancing cholinergic nerve activity and increasing nitric oxide synthase (NOS) activity to enhance insulin activity. Despite the well-documented effect of pain control by EA in many systemic diseases, there are few high-quality long-term clinical trials on the hypoglycemic effect of EA in DM. Combination treatment with EA and other medications seems to be an alternative treatment to achieve better therapeutic goals that merit future investigation.
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Identification and characterization of an asparaginyl endopeptidase from Angiostrongylus cantonensis.
Parasitol. Res.
PUBLISHED: 03-21-2014
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Asparaginyl endopeptidase, also known as legumain, is a family of cysteine proteases in many organisms. In this study, an asparaginyl endopeptidase (Ac-AEP) was identified from the cDNA library of Angiostrongylus cantonensis. The full-length of Ac-AEP was determined to be 1,472 bp with an open reading frame of 1,341 bp encoding a putative protein with 446 amino acids. This putative protein was determined to have 37-65% identity in the amino acid sequences of the asparaginyl endopeptidases of other parasitic helminths. By real-time quantitative PCR analysis, Ac-AEP was revealed to be more abundantly expressed in the female adult worms than in other development stages. A recombinant asparaginyl endopeptidase (rAc-AEP) was then produced by a Pichia pastoris expression system. Posttranslational modification was shown to occur via N-linked glycosylation in this recombinant enzyme. The proteolytic activity of rAc-AEP was inhibited by iodoacetamide but not affected by E64, pepatain A, AEBSF, and EDTA. Moreover, the purified rAc-AEP was recognized by IgG in serum samples from BALB/c or ICR mice with A. cantonensis infection and patients with eosinophilic meningitis. These findings indicate that the rAc-AEP may have the potential for detecting A. cantonensis infection.
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The association of peptic ulcer and schizophrenia: A population-based study.
J Psychosom Res
PUBLISHED: 03-13-2014
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The association of schizophrenia with peptic ulcer is not conclusive. In the last 30years, there has been little evaluation of peptic ulcer among schizophrenia patients.
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A prospective and randomized comparison of limited versus extensive atrial substrate modification after circumferential pulmonary vein isolation in nonparoxysmal atrial fibrillation.
J. Cardiovasc. Electrophysiol.
PUBLISHED: 02-27-2014
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The optimal substrate ablation approach in patients with persistent atrial fibrillation (Per AF) remains unclear. This was a prospective randomized study comparing the efficacy of limited (continuous complex fractionated atrial electrogram, CFAE: <60 milliseconds) versus extensive (continuous CFAE plus variable CFAE: <120 milliseconds) atrial substrate modification in Per AF patients.
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Impact of renal dysfunction on clinical outcome in patients with low risk of atrial fibrillation.
Circ. J.
PUBLISHED: 02-13-2014
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?The impact of renal dysfunction has been investigated in patients with non-valvular atrial fibrillation (AF). The aim of this study was to assess its additive prognostic value in low thromboembolic risk AF patients with CHA2DS2-VASc score 0-1.
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Improved measurement of camera response function and its performance evaluation.
Appl Opt
PUBLISHED: 02-12-2014
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Estimation of camera response function (CRF) has become important in the field of computer graphics and radiance measurement to achieve accurate modeling and high dynamic range imaging. A method is proposed to provide accurate radiance for direct measurement of the CRF in this paper by using a polariscope. The experimental results indicate that the accuracy of the estimated CRF obtained by the new approach is about 5% better than that of the previous method.
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Amiodarone-induced thyroid dysfunction in Taiwan: a retrospective cohort study.
Int J Clin Pharm
PUBLISHED: 02-11-2014
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The incidence and risk factors of amiodarone-induced thyroid dysfunction are variable in the literature.
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Risk stratification of arrhythmogenic right ventricular cardiomyopathy based on signal averaged electrocardiograms.
Int. J. Cardiol.
PUBLISHED: 01-27-2014
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Signal averaged electrocardiogram (SAECG) is a specific and non-invasive tool useful for arrhythmogenic right ventricular cardiomyopathy (ARVC) diagnosis. However, its role in risk stratification of patients with ARVC remains largely undefined.
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Peroxisome proliferator-activated receptor activating hypoglycemic effect of Gardenia jasminoides Ellis aqueous extract and improvement of insulin sensitivity in steroid induced insulin resistant rats.
BMC Complement Altern Med
PUBLISHED: 01-15-2014
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The active components of Gardenia (Gardenia jasminoides Ellis, GJ) exhibit a hypoglycemic effect by improving insulin secretion and lowering plasma lipids. In the present study, we fed a water extract of gardenia to steroid-induced insulin-resistant (SIIR) rats and observed changes in signaling proteins in order to elucidate the mechanisms of the insulin-sensitizing effect of GJ and evaluate its possibility as an insulin-sensitizing agent.
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Does digoxin increase the risk of ischemic stroke and mortality in atrial fibrillation? A nationwide population-based cohort study.
Can J Cardiol
PUBLISHED: 01-10-2014
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Digoxin and related cardiac glycosides have been used for almost 100 years in atrial fibrillation (AF). However, 2 recent analyses of the Atrial Fibrillation Follow-Up Investigation of Rhythm Management (AFFIRM) trial showed inconsistent results regarding the risk of mortality associated with digoxin use. The goal of the present study was to investigate the relationship between digoxin and the risk of ischemic stroke and mortality in Asians.
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R2CHADS2 score and thromboembolic events after catheter ablation of atrial fibrillation in comparison with the CHA2DS2-VASc score.
Can J Cardiol
PUBLISHED: 01-09-2014
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A new risk model, the R2CHADS2 (Renal Dysfunction, Congestive Heart Failure, Hypertension, Age, Diabetes, Stroke/Transient Ischemic Attack) score, was proposed to be a powerful scoring scheme in predicting stroke or systemic embolism in atrial fibrillation (AF). The goal of the present study is to validate the usefulness of the R2CHADS2 score among patients with AF after catheter ablation. We also aimed to compare the accuracy of the CHA2DS2-VASc (Congestive Heart Failure, Hypertension, Age [? 75 y], Diabetes, Stroke/Transient Ischemic Attack, Vascular Disease, Age [65-74 y], Sex [Female]) and R2CHADS2 scores for risk stratification of thromboembolic (TE) events after ablation procedures.
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The effects of gout on left atrial volume remodelling: a prospective echocardiographic study.
Rheumatology (Oxford)
PUBLISHED: 01-09-2014
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The aim of the present study was to investigate the effect of gout on left ventricular (LV) diastolic function and left atrial volume (LAV).
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Impact of gout on left atrial function: a prospective speckle-tracking echocardiographic study.
PLoS ONE
PUBLISHED: 01-01-2014
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The purpose of our study was to evaluate the left ventricular (LV) and left atrial (LA) function in patients with gout. A total of 173 patients underwent a comprehensive Doppler-echocardiography examination. Participants were divided into four groups-Stage 0: control (n = 35), Stage I: asymptomatic hyperuricemia (n = 30), Stage II: gouty arthritis without tophi (n = 58), and Stage III: tophaceous gout (n = 50). Serum uric acid levels were not significantly different between stage I, II and III. Stage III patients demonstrated a higher ratio of the transmitral and myocardial peak early diastolic velocities (E/Em) (10.50 ± 3.18 vs. 8.58 ± 2.07; P = 0.008), and larger maximal LA volume index (LAVi) (29.60 ± 9.89 vs. 20.07 ± 4.76 ml/m(2); P<0.001) compared with controls. Stage III patients had decreased LV global longitudinal systolic strain (LV?) compared with controls (-20.2 ± 3.06 vs. -21.79 ± 2.27; P = 0.002). Stage III patients also had decreased peak atrial longitudinal strain rate during ventricular systole (ALSR(syst)), peak atrial longitudinal strain rate during ventricular early diastole (ALSR(early)), and peak atrial longitudinal strain rate during ventricular late diastole (ALSR(late)) compared with controls (1.73 ± 0.48 vs. 2.05 ± 0.55 1/s, -1.44 ± 0.53 vs. -2.07 ± 0.84 1/s, -2.07 ± 0.7 vs. -2.66 ± 0.91 1/s, respectively; all P<0.005). Multiple regression analysis revealed severity of gout had an independent negative impact on LA pump function (ALSR(late)). In conclusion, gout caused LV diastolic dysfunction, LV subclinical systolic dysfunction and LA reservoir, conduit, and booster pump dysfunction.
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Relationship between resistant hypertension and arterial stiffness assessed by brachial-ankle pulse wave velocity in the older patient.
Clin Interv Aging
PUBLISHED: 01-01-2014
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Resistant hypertension (RH) is a common clinical condition associated with increased cardiovascular mortality and morbidity in older patients. Several factors and conditions interfering with blood pressure (BP) control, such as excess sodium intake, obesity, diabetes, older age, kidney disease, and certain identifiable causes of hypertension are common in patients resistant to antihypertensive treatment. Arterial stiffness, measured by brachial-ankle pulse wave velocity (baPWV), is increasingly recognized as an important prognostic index and potential therapeutic target in hypertensive patients. The aim of this study was to determine whether there is an association between RH and arterial stiffness.
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The association between atrium electromechanical interval and pericardial fat.
PLoS ONE
PUBLISHED: 01-01-2014
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Pericardial fat (PCF) may induce local inflammation and subsequent structural remodeling of the left atrium (LA). However, the adverse effects of PCF on LA are difficult to be evaluated and quantified. The atrial electromechanical interval determined by transthoracic echocardiogram was shown to be a convenient parameter which can reflect the process of LA remodeling. The goal of the present study was to investigate the association between the electromechanical interval and PCF.
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Higher risk for meningioma in women with uterine myoma: a nationwide population-based retrospective cohort study.
J. Neurosurg.
PUBLISHED: 12-06-2013
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Object Evidence suggests that hormones play a role in modifying both uterine myoma (UM) and meningioma. A number of studies have observed the positive association between these diseases. The aim of the current population-based study was to determine if women with UM are at a higher risk for meningioma. Methods The authors used data from the National Health Insurance system of Taiwan for the study. The UM cohort contained 281,244 women. Each woman was randomly frequency-matched with 4 women without UM, based on age, index year of diagnosis, occupation, urbanization (urbanization level was categorized by the population density of the residential area into 4 levels, with Level 1 as the most urbanized and Level 4 as the least urbanized), and comorbidity, to form the control cohort. Coxs proportional hazard regression analysis was conducted to estimate the influence of UM on the meningioma risk. Results Among women with UM, the risk of developing meningioma was significantly higher (45%) than among women without UM (95% CI 1.23-1.70). The same phenomenon was observed among most age groups, but a significant difference was only seen in the middle-age range. For women with UM, further analysis did not show a significant change after myomectomy. The cumulative incidence of meningioma between groups with and without UM differed over time. Conclusions The nationwide population-based cohort study found that Taiwanese women with UM are at higher risk for developing meningioma.
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Prevalence, characteristics, mapping, and catheter ablation of potential rotors in nonparoxysmal atrial fibrillation.
Circ Arrhythm Electrophysiol
PUBLISHED: 08-27-2013
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Identification of critical atrial substrates in patients with nonparoxysmal atrial fibrillation (AF) failing to respond to pulmonary vein isolation is important. This study investigated the signal characteristics, substrate nature, and ablation results of rotors during AF.
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A nationwide population cohort study: Irritable bowel syndrome is a risk factor of osteoporosis.
Eur. J. Intern. Med.
PUBLISHED: 08-14-2013
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The goal of the study is to determine the relationship between irritable bowel syndrome (IBS) and osteoporosis in Taiwan.
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A transcriptomic analysis on gene expressions in the infective third and pathogenic fifth larval stages of Angiostrongylus cantonensis.
Parasitol. Int.
PUBLISHED: 08-12-2013
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Although Angiostrongylus cantonensis is a parasite of rats, it is an important etiologic agent of eosinophilic meningitis and eosinophilic meningoencephalitis in humans. This study was designed to compare the gene expression in the third- and fifth-stage (L3 and L5) by analysis of expressed sequence tags (ESTs). After removing low quality sequences, vector trimming, clustering and contig assembly, there remained 1437 clusters (285 contigs and 1152 singletons). Among these clusters, 779 (54.2%) showed significant similarity to the known proteins in the non-redundant protein database of GenBank (E-value<1×10(-10)) and species of the best hit sequences mainly belonged to nematodes. These clusters included 869 (60.5%) that were entirely comprised of ESTs from L3 (L3-biased clusters), 518 (36.0%) entirely from L5 (L5-biased clusters) and 50 (3.5%) from both stages (stage-shared clusters). Functional annotations by the Gene Ontology (GO) comparing with the eukaryotic clusters of orthologous groups of proteins (KOG) indicate that the L3-biased clusters significantly related to metabolism and the L5-biased clusters to growth, development, sexual differentiation and reproduction. Moreover, L3 were found to have expressions of metalloproteases, aspartic proteases, and cysteine proteases whereas expressions of cysteine, aspartic and serine proteases were revealed in L5. The results indicate that earlier developmental stages of nematodes may have a gene expression profile towards metabolism and later stages towards growth and development.
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Electromechanical Effects of 1,25-Dihydroxyvitamin D with Antiatrial Fibrillation Activities.
J. Cardiovasc. Electrophysiol.
PUBLISHED: 07-23-2013
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Treatment with 1,25-dihydroxyvitamin D (1,25[OH]2 D) has several cardiovascular benefits. 1,25[OH]2 D has direct cellular effects, but its effects on the atrium are not clear. We evaluated the effects of 1,25[OH]2 D on the atrial electrophysiology and atrial fibrillation (AF).
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Identification and characterisation of microRNAs in young adults of Angiostrongylus cantonensis via a deep-sequencing approach.
Mem. Inst. Oswaldo Cruz
PUBLISHED: 06-13-2013
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Angiostrongylus cantonensis is an important causative agent of eosinophilic meningitis and eosinophilic meningoencephalitis in humans. MicroRNAs (miRNAs) are small non-coding RNAs that participate in a wide range of biological processes. This study employed a deep-sequencing approach to study miRNAs from young adults of A. cantonensis. Based on 16,880,456 high-quality reads, 252 conserved mature miRNAs including 10 antisense miRNAs that belonging to 90 families, together with 10 antisense miRNAs were identified and characterised. Among these sequences, 53 miRNAs from 25 families displayed 50 or more reads. The conserved miRNA families were divided into four groups according to their phylogenetic distribution and a total of nine families without any members showing homology to other nematodes or adult worms were identified. Stem-loop real-time polymerase chain reaction analysis of aca-miR-1-1 and aca-miR-71-1 demonstrated that their level of expression increased dramatically from infective larvae to young adults and then decreased in adult worms, with the male worms exhibiting significantly higher levels of expression than female worms. These findings provide information related to the regulation of gene expression during the growth, development and pathogenesis of young adults of A. cantonensis.
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A novel finding- impairment of gastric myoelectricity after catheter ablation of atrial fibrillation.
Circ. J.
PUBLISHED: 05-23-2013
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Dyspepsia is not uncommon in patients undergoing ablation of atrial fibrillation (AF). The purpose of this study was to investigate the change in gastric myoelectrical activity and its relationship to the outcome after ablation by electrogastrography (EGG). MethoDS AND RESULTS: The study prospectively enrolled 32 patients: 16 patients (Group 1) had AF and 16 (Group 2) had paroxysmal supraventricular tachycardia. The myoelectricity-like signals of the gastrointestinal tract were recorded using EGG before, immediately, and 3 months after ablation. Both fasting and postprandial abnormal gastric wave percentages increased immediately after ablation in Group 1 when compared with before ablation. Increased fasting (12.8 ± 15.2% vs. 22.3 ± 21.0%, P=0.04) and postprandial (10.4 ± 6.2% vs. 21.2 ± 14.5%, P=0.01) bradygastria percentages were noted immediately after ablation in Group 1 when compared with before ablation. These findings were not observed in Group 2. The normal gastric wave percentage returned to baseline 3 months after procedure. In total, 4 (25%) patients in Group 1 had a recurrence of AF after a follow-up of 18 ± 3 months; those without recurrence had a significantly higher percentage of postprandial abnormal gastric waves immediately after ablation when compared with recurrence.
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Aqueous extracts of Cordyceps militaris (Ascomycetes) lower the levels of plasma glucose by activating the cholinergic nerve in streptozotocin-induced diabetic rats.
Int J Med Mushrooms
PUBLISHED: 05-14-2013
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In our previous research, Cordyceps militaris (CM) had a hypoglycemic effect in normal rats. In this study we wanted to elucidate whether CM also had an effect on diabetic rats. Twelve rats with streptozotocin-induced diabetes were separated randomly into 2 groups. First, aqueous extracts of CM 10 mg/kg (CM group) or saline (control group) was fed to the rats; then the plasma glucose levels were assayed. Second, the signaling proteins IRS-1 and GLUT-4 collected from the muscle were detected. Finally, another 2 groups of rats were injected with atropine 0.1 mg/kg intraperitoneally just before the CM/saline feeding, and the assays mentioned above were repeated. Blood glucose decreased 7.2% in the CM group but only 1.5% in the control group (P < 0.05). The IRS-1 signal was 2.9-fold higher than actin in the CM group but only 0.8-fold higher in the control group (P < 0.005). In GLUT-4 signal, the difference was 1.7- vs. 0.6-fold, respectively, compared with actin (P < 0.05). However, atropine injection made CM-induced hypoglycemia or elevation of IRS-1 and GLUT-4 not significant. In conclusion, CM had a hypoglycemic effect in diabetic rats and atropine blocked it. Therefore, the cholinergic activation also was considered to be involved in the hypoglycemic effect of CM in rats with streptozotocin-induced diabetes.
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Influence of atrial fibrillation on survival in patients with hepatocellular carcinoma: Experience from a single center in Taiwan.
J Chin Med Assoc
PUBLISHED: 05-09-2013
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It is unclear whether atrial fibrillation (AF) adversely influences the clinical course of patients with hepatocellular carcinoma (HCC).
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Transcriptome profiling of the fifth-stage larvae of Angiostrongylus cantonensis by next-generation sequencing.
Parasitol. Res.
PUBLISHED: 03-22-2013
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Angiostrongylus cantonensis is an important zoonotic nematode. It is the causative agent of eosinophilic meningitis and eosinophilic meningoencephalitis in humans. However, information of this parasite at the genomic level is very limited. In the present study, the transcriptomic profiles of the fifth-stage larvae (L5) of A. cantonensis were investigated by next-generation sequencing (NGS). In the NGS database established from the larvae isolated from the brain of Sprague-Dawley rats, 31,487 unique genes with a mean length of 617 nucleotides were assembled. These genes were found to have a 46.08% significant similarity to Caenorhabditis elegans by BLASTx. They were then compared with the expressed sequence tags of 18 other nematodes, and significant matches of 36.09-59.12% were found. Among these genes, 3,338 were found to participate in 124 Kyoto Encyclopedia of Genes and Genomes pathways. These pathways included 1,514 metabolisms, 846 genetic information processing, 358 environmental information processing, 264 cellular processes, and 91 organismal systems. Analysis of 30,816 sequences with the gene ontology database indicated that their annotations included 5,656 biological processes (3,364 cellular processes, 3,061 developmental processes, and 3,191 multicellular organismal processes), 7,218 molecular functions (4,597 binding and 3,084 catalytic activities), and 4,719 cellular components (4,459 cell parts and 4,466 cells). Moreover, stress-related genes (112 heat stress and 33 oxidation stress) and genes for proteases (159) were not uncommon. This study is the first NGS-based study to set up a transcriptomic database of A. cantonensis L5. The results provide new insights into the survival, development, and host-parasite interactions of this blood-feeding nematode.
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The association between hyperuricemia, left atrial size and new-onset atrial fibrillation.
Int. J. Cardiol.
PUBLISHED: 03-17-2013
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Although hyperuricemia was associated with several cardiovascular diseases, the role of uric acid (UA) in left atrial (LA) remodeling and new-onset atrial fibrillation (AF) has not been fully explored. The goal of the present study is to investigate the relationship between UA, LA diameter and the development of AF in the large-scale cohort.
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Characterization of electrospun nanofiber matrices made of collagen blends as potential skin substitutes.
Biomed Mater
PUBLISHED: 02-22-2013
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Collagen and its blends, collagen/polyvinyl alcohol (PVA) and collagen/chitosan/PVA, were made into nanofibers by electrospinning. The nanofibrous matrices were evaluated for their potential as skin substitutes. The addition of PVA to collagen increased the swelling ratio of the nanofibers, their Youngs modulus, strain at break and ultimate tensile strength. The addition of chitosan to collagen/PVA reduced its swelling ratio and its strain at break, but increased the Youngs modulus and ultimate tensile strength. Both PVA and chitosan stabilized the collagen fibers in an aqueous solution. The addition of PVA, but not chitosan, promoted initial fibroblast cell proliferation on the matrices. Compared to the skin substitute made of pure collagen, the substitutes with PVA and chitosan showed improved structural stability in aqueous solution, better tensile strength and similar or better biocompatibility in vitro.
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Electroacupuncture and rosiglitazone combined therapy as a means of treating insulin resistance and type 2 diabetes mellitus: a randomized controlled trial.
Evid Based Complement Alternat Med
PUBLISHED: 02-21-2013
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Aims. To evaluate the efficacy of rosiglitazone (TZD) and electroacupuncture (EA) combined therapy as a treatment for type 2 diabetes mellitus (T2DM) patients by randomized single-blind placebo controlled clinical trial. Methods. A total of 31 newly diagnostic T2DM patients, who fulfilled the studys eligibility criteria, were recruited. The individuals were randomly assigned into two groups, the control group (TZD, N = 15) and the experimental group (TZD + EA, N = 16). Changes in their plasma free fatty acid (FFA), glucose, and insulin levels, together with their homeostasis model assessment (HOMA) indices, were statistically compared before and after treatment. Hypoglycemic activity (%) was also compared between these two groups. Results. There was no significant difference in hypoglycemic activity between the TZD and TZD + EA group. The effectiveness of the combined therapy seems to derive from an improvement in insulin resistance and a significant lowering of the secreted insulin rather than the effect of TZD alone on T2DM. The combined treatment had no significant adverse effects. A lower plasma FFA concentration is likely to be the mechanism that causes this effect. Conclusion. This combined therapy seems to suppress endogenous insulin secretion by improving insulin resistance via a mechanism involving a reduction in plasma FFA. This trial is registered with ClinicalTrials.gov NCT01577095.
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Functional characterization of atrial electrograms in a pacing-induced heart failure model of atrial fibrillation: importance of regional atrial connexin40 remodeling.
J. Cardiovasc. Electrophysiol.
PUBLISHED: 02-19-2013
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Heart failure (HF) increases the susceptibility to atrial fibrillation (AF) and is associated with altered cardiomyocyte connexin. The regional remodeling of connexin(s) may contribute to the spatiotemporal organization of AF. This study sought to investigate the regional differences in connexin(s) and fibrosis in specific atrial regions and correlate that with the electrogram properties.
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Heat shock protein inducer modifies arrhythmogenic substrate and inhibits atrial fibrillation in the failing heart.
Int. J. Cardiol.
PUBLISHED: 02-07-2013
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Geranylgeranylacetone (GGA) has been reported up-regulating heat shock protein (HSP) expression, and protecting against atrial remodeling. This study aimed to investigate the effects of GGA on atrial electrophysiology and inducibility of atrial fibrillation (AF) in heart failure (HF) model.
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The utilization of twelve-lead electrocardiography for predicting sudden cardiac death after heart transplantation.
Int. J. Cardiol.
PUBLISHED: 02-06-2013
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Sudden cardiac death (SCD) occurs commonly after heart transplantation (HTX). The utilization of surface electrocardiography (ECG) to assess post-HTX SCD has not been investigated thoroughly. This study aimed to investigate the specific changes in surface ECG in HTX patients with SCD.
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Hyperuricemia and the risk of ischemic stroke in patients with atrial fibrillation - Could it refine clinical risk stratification in AF?
Int. J. Cardiol.
PUBLISHED: 01-31-2013
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Although hyperuricemia has been reported to be a risk factor of stroke, the relationship between hyperuricemia and stroke in patients with atrial fibrillation (AF) remains uncertain. The goal of the present study was to investigate whether hyperuricemia could potentially refine clinical risk stratification in AF.
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Electrophysiological characteristics of complex fractionated electrograms and high frequency activity in atrial fibrillation.
Int. J. Cardiol.
PUBLISHED: 01-18-2013
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It is unclear whether atrial substrate with complex fractionated electrograms (CFAEs) is related to arrhythmogenesis. This study aimed to investigate the electrophysiology in CFAE and high dominant frequency (DF) areas.
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Differences in high on-treatment platelet reactivity between intra-coronary and peripheral blood after dual anti-platelet agents in patients with coronary artery disease.
Thromb. Haemost.
PUBLISHED: 01-13-2013
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The differences of high on-treatment platelet reactivity (HPR) between the coronary arteries and peripheral veins might be associated with poor prediction of adverse cardiovascular events in patients with coronary artery diseases. HPR from the peripheral blood might not adequately reflect the platelet responses in the coronary artery. A total of 21 patients were recruited, and regional differences in HPR were compared between blood samples from the intra-coronary artery (IC), femoral artery (FA), and femoral vein (FV) by light aggregometry (agonists: arachidonic acid, LTA-AA; ADP, LTA-ADP), VerifyNow P2Y12 assays, and a platelet function analyser (PFA-100, collagen and epinephrine cartridge, PFA-CEPI). There were regional differences in the platelet reactivities observed by LTA-AA, VerifyNow P2Y12 assays, and PFA-CEPI. Platelets from the IC had higher platelet reactivities than those from the FV and FA by the VerifyNow P2Y12 assays but lower reactivities by LTA-AA and PFA-CEPI. HPR values from the blood in the FA were more similar to those from the IC than those from the FV by any test. The monocyte percentages were the only factors associated with differences in HPR between the FV and IC by the VerifyNow P2Y12 assays. Triglyceride levels were associated with the differences in HPR between the FV and IC by LTA-ADP. During the six-month follow-up period, two patients developed cardiovascular events and exhibited differences in HPR between different sites by VerifyNow P2Y12 assays. In conclusions, there were regional differences in HPR in patients with coronary artery diseases, which might prevent the adequate prediction of cardiovascular events.
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Different effects of dronedarone and amiodarone on pulmonary vein electrophysiology, mechanical properties and H2O2-induced arrhythmogenicity.
Eur. J. Pharmacol.
PUBLISHED: 01-10-2013
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Dronedarone and amiodarone are anti-atrial fibrillation agents with different potency. Pulmonary veins play a critical role in the genesis of atrial fibrillation. Oxidative stress can enhance pulmonary vein arrhythmogenesis. This study was done to compare the effects of dronedarone and amiodarone on pulmonary vein electrophysiological and mechanical properties, and oxidative stress-induced arrhythmogenecity. Conventional microelectrodes were used to record action potentials in isolated rabbit pulmonary vein specimens before and after dronedarone and amiodarone with or without the presence of H2O2 (2mM). Dronedarone (0.1, 1 and 10 ?M) concentration-dependently decreased pulmonary vein beating rates (from 2.2±0.1 to 1.9±0.1, 1.8±0.1 and 1.7±0.1Hz, n=8, P<0.01). Amiodarone (0.1, 1 and 10 ?M) also concentration-dependent decreased pulmonary vein beating rates (from 2.5±0.2 to 2.3±0.2, 2.2±0.2 and 2.0±0.2Hz, n=7, P<0.01). However, dronedarone decreased pulmonary vein beating rates to a greater extent at 0.1 ?M (12% versus 4%, P<0.005) and 1?M (17% versus 9%, P<0.005). Dronedarone or amiodarone (0.1, 1 and 10 ?M) did not change the pulmonary vein contractility. However, dronedarone (1 and 10 ?M) concentration-dependent reduced pulmonary vein diastolic tension by 13±2 mg (P<0.005) and 18±3 mg (P<0.005). In contrast, amiodarone did not change pulmonary vein diastolic tension. Dronedarone (10 ?M) and amiodarone (10 ?M) attenuated H2O2-induced pulmonary vein burst firings from 100% to 33.3% (P<0.01), and to 0% (P<0.005), respectively. In conclusion, amiodarone and dronedarone both significantly reduced pulmonary vein spontaneous beating rates and H2O2-induced pulmonary vein arrhythmogenesis. However, only dronedarone produced pulmonary vein vasodilation.
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The association between heme oxygenase-1 gene promoter polymorphism and the outcomes of catheter ablation of atrial fibrillation.
PLoS ONE
PUBLISHED: 01-08-2013
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A length polymorphism of GT repeats in the promoter region of the human heme oxygenase-1 (HO-1) gene modulates its gene transcription to protect against myocardial injury. The present study investigated the association between HO-1 promoter polymorphisms and the outcomes of catheter ablation of atrial fibrillation (AF). The allelic frequencies of GT repeats in the HO-1 gene promoter were screened in 205 random individuals who underwent catheter ablation for drug refractory AF.In the patients who received catheter ablation, those with AF recurrence had fewer GT repeats (53.4±7.1 vs. 56.1±6.5, p = 0.004), a lower incidence of hyperlipidemia, more non-paroxysmal AF, and a larger left atrial diameter. After conducting a multivariate logistic analysis, the number of GT repeats (Odds ratio: 0.94, 95% CI 0.90-0.99, p = 0.01) and the diameter of the left atrium (Odds ratio: 1.08, 95% CI 1.02-1.15, p = 0.01) remained independent predictors. The carriers of GT repeats, which were <29 in both alleles, were associated with a lower sinus maintenance rate after catheter ablation (38.5% vs. 60.1%, p = 0.003). The patients were divided into paroxysmal and non-paroxysmal AF groups; the number of GT repeats was associated with AF recurrence only in the patients with paroxysmal AF. The number of GT repeats, combined with LAD, was significant for predicting AF recurrence after catheter ablation (p = 0.01). The number of GT repeats was not found to be associated with differences in the left atrial diameter, the biatrial voltage, or the levels of bilirubin, ferritin, iron, C-reactive protein, or von-Willibrand factor. In conclusions, HO-1 gene promoter polymorphisms were associated with AF recurrence after catheter ablation.
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The relationship among atrium electromechanical interval, insulin resistance, and metabolic syndrome.
Can J Cardiol
PUBLISHED: 01-02-2013
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Metabolic syndrome (MS) is an important risk factor of atrial fibrillation. However, an understanding of the adverse effects of MS on left atrial (LA) functional assessment in terms of electromechanical interval, a convenient parameter that can reflect the process of LA remodelling, has been lacking. The goal of this study was to investigate the association between electromechanical interval and MS.
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Differences in the atrial electrophysiological properties between vagal and sympathetic types of atrial fibrillation.
J. Cardiovasc. Electrophysiol.
PUBLISHED: 01-02-2013
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Autonomic modulation of the cardiac activity plays an important role in the pathogenesis of atrial fibrillation (AF). The aim of this study was to assess the differences in the atrial electrical and structural properties between patients with vagal and sympathetic AF.
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A potent and selective Peptide blocker of the kv1.3 channel: prediction from free-energy simulations and experimental confirmation.
PLoS ONE
PUBLISHED: 01-01-2013
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The voltage-gated potassium channel Kv1.3 is a well-established target for treatment of autoimmune diseases. ShK peptide from a sea anemone is one of the most potent blockers of Kv1.3 but its application as a therapeutic agent for autoimmune diseases is limited by its lack of selectivity against other Kv channels, in particular Kv1.1. Accurate models of Kv1.x-ShK complexes suggest that specific charge mutations on ShK could considerably enhance its specificity for Kv1.3. Here we evaluate the K18A mutation on ShK, and calculate the change in binding free energy associated with this mutation using the path-independent free energy perturbation and thermodynamic integration methods, with a novel implementation that avoids convergence problems. To check the accuracy of the results, the binding free energy differences were also determined from path-dependent potential of mean force calculations. The two methods yield consistent results for the K18A mutation in ShK and predict a 2 kcal/mol gain in Kv1.3/Kv1.1 selectivity free energy relative to wild-type peptide. Functional assays confirm the predicted selectivity gain for ShK[K18A] and suggest that it will be a valuable lead in the development of therapeutics for autoimmune diseases.
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Epicardial adipose tissue thickness and ablation outcome of atrial fibrillation.
PLoS ONE
PUBLISHED: 01-01-2013
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Epicardial fat was closely related to atrial fibrillation (AF). Transthoracic echocardiography (TTE) has been proposed to be a convenient imaging tool in assessing epicardial adipose tissue (EAT). The goal of the present study was to investigate whether the EAT thickness measured on TTE was a useful parameter in predicting procedural outcomes of AF ablations.
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Plasma asymmetric dimethylarginine and adverse events in patients with atrial fibrillation referred for coronary angiogram.
PLoS ONE
PUBLISHED: 01-01-2013
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Elevated plasma levels of asymmetric dimethylarginine (ADMA) have been reported to be associated with endothelial dysfunction, inflammation, and oxidative stress in multiple cardiovascular diseases. This study aimed to investigate whether ADMA was a predictor of clinical outcomes in atrial fibrillation (AF).
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Heart failure enhanced pulmonary vein arrhythmogenesis and dysregulated sodium and calcium homeostasis with increased calcium sparks.
J. Cardiovasc. Electrophysiol.
PUBLISHED: 10-12-2011
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Late sodium currents and intracellular Ca(2+) (Ca(2+) (i)) dynamics play an important role in arrhythmogenesis of pulmonary vein (PV) and heart failure (HF). It is not clear whether HF enhances PV arrhythmogenesis through modulation of Ca(2+) homeostasis and increased late sodium currents. The aim of this study was to investigate the sodium and calcium homeostasis in PV cardiomyocytes with HF.
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Improvement of digital photoelasticity based on camera response function.
Appl Opt
PUBLISHED: 09-28-2011
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Studies on photoelasticity have been conducted by many researchers in recent years, and many equations for photoelastic analysis based on digital images were proposed. While these equations were all presented by the light intensity emitted from the analyzer, pixel values of the digital image were actually used in the real calculations. In this paper, a proposal of using relative light intensity obtained by the camera response function to replace the pixel value for photoelastic analysis was investigated. Generation of isochromatic images based on relative light intensity and pixel value were compared to evaluate the effectiveness of the new approach. The results showed that when relative light intensity was used, the quality of an isochromatic image can be greatly improved both visually and quantitatively. We believe that the technique proposed in this paper can also be used to improve the performance for the other types of photoelastic analysis using digital images.
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A novel finding of the atrial substrate properties and long-term results of catheter ablation in chronic atrial fibrillation patients with left atrial spontaneous echo contrast.
J. Cardiovasc. Electrophysiol.
PUBLISHED: 09-13-2011
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The atrial substrate in chronic atrial fibrillation (AF) patients with a left atrial spontaneous echo contrast (LASEC) has not been previously reported. The aim of this study was to investigate the atrial substrate properties and long-term follow-up results in the patients who received catheter ablation of chronic AF.
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Prognostic value of QT dispersion change following primary percutaneous coronary intervention in acute ST elevation myocardial infarction.
Int Heart J
PUBLISHED: 08-11-2011
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This study analyzed the corrected QT dispersion (cQTd) before and at 24 hours after successful primary percutaneous coronary intervention (PCI) in 81 patients with single coronary artery disease and acute ST elevation myocardial infarction. Major cardiovascular events (MACE) at 1 year were defined as death, nonfatal myocardial infarction, life-threatening arrhythmias, and heart failure hospitalization. The cQTd before primary PCI was significantly longer in patients without MACE than in patients with MACE (73.1 ± 29.3 versus 56.3 ± 25.2 msec, P = 0.026). The cQTd at 24 hours after primary PCI was significantly shorter in patients without MACE than in patients with MACE (38.4 ± 20.8 versus 50.8 ± 28.7 msec, P = 0.045). Thus, the absolute cQTd change was significantly higher in patients without MACE compared to patients with MACE (P = 0.001). By multivariate analysis, absolute cQTd change was an independent predictor for the development of MACE, with an odds ratio of 1.498 for each 10-msec decrement in absolute cQTd change (95 percent confidence interval, 1.157 to 1.939, P = 0.002). In conclusion, the absolute cQTd change after primary PCI was an independent predictor of the development of MACE in patients with single vessel disease and acute ST elevation myocardial infarction.
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Associations between renal function, atrial substrate properties and outcome of catheter ablation in patients with paroxysmal atrial fibrillation.
Circ. J.
PUBLISHED: 07-20-2011
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Renal dysfunction was reported to be associated with a higher recurrence rate after electric cardioversion of atrial fibrillation (AF). The aim of this study was to investigate the associations between renal function, atrial substrate properties and outcome of catheter ablation in paroxysmal AF patients.
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Association between chronic viral hepatitis infection and breast cancer risk: a nationwide population-based case-control study.
BMC Cancer
PUBLISHED: 07-14-2011
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In Taiwan, there is a high incidence of breast cancer and a high prevalence of viral hepatitis. In this case-control study, we used a population-based insurance dataset to evaluate whether breast cancer in women is associated with chronic viral hepatitis infection.
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RBAC-Matrix-based EMR right management system to improve HIPAA compliance.
J Med Syst
PUBLISHED: 06-30-2011
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Security control of Electronic Medical Record (EMR) is a mechanism used to manage electronic medical records files and protect sensitive medical records document from information leakage. Researches proposed the Role-Based Access Control(RBAC). However, with the increasing scale of medical institutions, the access control behavior is difficult to have a detailed declaration among roles in RBAC. Furthermore, with the stringent specifications such as the U.S. HIPAA and Canada PIPEDA etc., patients are encouraged to have the right in regulating the access control of his EMR. In response to these problems, we propose an EMR digital rights management system, which is a RBAC-based extension to a matrix organization of medical institutions, known as RBAC-Matrix. With the aim of authorizing the EMR among roles in the organization, RBAC-Matrix also allow patients to be involved in defining access rights of his records. RBAC-Matrix authorizes access control declaration among matrix organizations of medical institutions by using XrML file in association with each EMR. It processes XrML rights declaration file-based authorization of behavior in the two-stage design, called master & servant stage, thus makes the associated EMR to be better protected. RBAC-Matrix will also make medical record file and its associated XrML declaration to two different EMRA(EMR Authorization)roles, namely, the medical records Document Creator (DC) and the medical records Document Right Setting (DRS). Access right setting, determined by the DRS, is cosigned by the patient, thus make the declaration of rights and the use of EMR to comply with HIPAA specifications.
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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.