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Find video protocols related to scientific articles indexed in Pubmed.
Osteoporosis increases subsequent risk of gallstone: a nationwide population-based cohort study in Taiwan.
BMC Gastroenterol
PUBLISHED: 11-18-2014
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BackgroundOsteopontin (OPN) is a pro-inflammatory cytokine which is expressed in various tissues. It participates in the bone remodeling process and stimulates bone resorption by osteoclasts. It is also a core protein of cholesterol gallstones. We hypothesized osteoporotic patients might have higher risk in developing gallstones and conducted a population-based study to examine the risk of developing gallstone in osteoporotic patients in Taiwan.MethodsA total of 1,638 patients diagnosed with osteoporosis between 2003 and 2005 were identified in the National Health Insurance Research Database. A comparison cohort without osteoporosis (n =6,552) was randomly matched to each osteoporosis patient at a ratio of 4: 1 based on age and sex. A Cox proportional-hazards regression analysis was performed to evaluate the 5-year gallstone-free survival rates for the 2 cohorts.ResultsDuring the 5-year follow-up period, 114 and 311 cases of gallstone occurred in the osteoporosis and comparison cohorts, respectively. After adjusting for the confounders, the Cox regression analysis of the risk of gallstone in the osteoporosis and comparison cohorts yielded a hazard ratio of 1.35 (95% confidence interval: 1.07 - 1.69; p < 0 .01).ConclusionPatients with osteoporosis in Taiwan have a higher risk of developing gallstone than the general population.
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Electron-hole plasma induced band gap renormalization in ZnO microlaser cavities.
Opt Express
PUBLISHED: 11-18-2014
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We report electron-hole plasma (EHP) lasing in hexagonal ZnO microrods and thin nanobelts. Under the excitation of 325 nm line femtosecond pulsed laser, ultraviolet whispering-gallery mode (WGM) lasing was observed from hexagonal ZnO microrods. When EHP was formed at high excitation energy density, the center wavelength of the WGM lasing band presented a redshift from 387.5 nm to 397.5 nm, and the full width of half maximum (FWHM) of the WGM lasing band increased from 2.5 nm to 7 nm. Each lasing mode showed obvious blueshift and broadening. Such lasing characteristics were attributed to the band gap renormalization (BGR) due to the high carrier concentration at the EHP condition. In addition, EHP Fabry-Perot (F-P) mode lasing from thin ZnO nanobelt was also observed and discussed. According to the phenomenological BGR calculation with including the carrier density dependent screening effect, the values of the band gap of ZnO at different excitation energy densities were obtained, which agree well with the experimental results.
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In Vivo Pancreatic ? Cell-Specific Expression of Anti-aging Gene Klotho, A Novel Approach for Preserving ? Cells in Type II Diabetes.
Diabetes
PUBLISHED: 11-08-2014
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Protein expression of an anti-aging gene Klotho was depleted in pancreatic islets in patients with type 2 diabetes mellitus (T2DM) and in db/db mice, an animal model of T2DM. The objective of this study is to investigate if in vivo expression of Klotho would preserve pancreatic ? cell function in db/db mice. Here, we report for the first time that ? cell-specific expression of Klotho attenuated the development of diabetes in db/db mice. ? cell-specific expression of Klotho decreased hyperglycemia and enhanced glucose tolerance. The beneficial effects of Klotho were associated with significant improvements in T2DM-induced decreases in the number of ? cells, insulin storage levels in pancreatic islets, and glucose-stimulated insulin secretion from pancreatic islets which led to increased blood insulin levels in diabetic mice. In addition, ? cell-specific expression of Klotho decreased the intracellular superoxide levels, oxidative damage, apoptosis, and DNAJC3 (a marker for endoplasmic reticulum stress) in pancreatic islets. Furthermore, ? cell-specific expression of Klotho increased expression levels of Pdx-1 (insulin transcription factor), PCNA (a marker of cell proliferation), and LC3 (a marker of autophagy) in pancreatic islets in db/db mice. These results revealed that ? cell-specific expression of Klotho improved ? cell function and attenuated the development of T2DM. Therefore, in vivo expression of Klotho may offer a novel strategy for protecting ? cells in T2DM.
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Kinetics of organ response and survival following normalization of the serum free light chain ratio in AL amyloidosis.
Am. J. Hematol.
PUBLISHED: 11-06-2014
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Despite successful treatment of the clonal plasma cell implicated in its pathogenesis, patients with AL amyloidosis (AL) experience significant morbidity related to underlying amyloid mediated organ dysfunction. While normalization of the serum free light chain measurements (normal ratio of involved and uninvolved free light chains (nFLCr)) is the goal of therapy and centerpiece of hematologic response criteria, achieving (or not achieving) meaningful organ response (OR) is clinically significant for its implications on long-term symptomatology as well as overall survival, and remains the ultimate goal of treatment. Expectations for organ recovery following successful therapy leading to nFLCr in AL remain poorly described. We evaluated the timeframe and predictive factors for OR, and long-term outcome, in 313 AL patients who achieved nFLCr following therapy initiation. OR was seen in 80% of surviving AL patients within one-year of nFLCr. Patients achieving early OR within 1 year of nFLCr had superior overall survival (OS) compared to those who despite obtaining nFLCr did not achieve early OR. We further evaluated factors predicting OR and OS among patients achieving nFLCr. Higher values of dFLC (involved-uninvolved) at diagnosis predict organ response, and early OR predicts improved overall survival following successful hematologic therapy in AL.
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Measurement of extreme hyperfine fields in two-coordinate high-spin fe(2+) complexes by mössbauer spectroscopy: essentially free-ion magnetism in the solid state.
Inorg Chem
PUBLISHED: 11-04-2014
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Mössbauer studies of three two-coordinate linear high-spin Fe(2+) compounds, namely, Fe{N(SiMe3)(Dipp)}2 (1) (Dipp = C6H3-2,6-(i)Pr2), Fe(OAr')2 (2) [Ar' = C6H3-2,6-(C6H3-2,6-(i)Pr2)2], and Fe{C(SiMe3)3}2 (3), are presented. The complexes were characterized by zero- and applied-field Mössbauer spectroscopy (1-3), as well as zero- and applied-field heat-capacity measurements (3). As 1-3 are rigorously linear, the distortion(s) that might normally be expected in view of the Jahn-Teller theorem need not necessarily apply. We find that the resulting very large unquenched orbital angular momentum leads to what we believe to be the largest observed internal magnetic field to date in a high-spin iron(II) compound, specifically +162 T in 1. The latter field is strongly polarized along the directions of the external field for both longitudinal and transverse field applications. For the longitudinal case, the applied field increases the overall hyperfine splitting consistent with a dominant orbital contribution to the effective internal field. By contrast, 2 has an internal field that is not as strongly polarized along a longitudinally applied field and is smaller in magnitude at ca. 116 T. Complex 3 behaves similarly to complex 1. They are sufficiently self-dilute (e.g., Fe···Fe distances of ca. 9-10 Å) to exhibit varying degrees of slow paramagnetic relaxation in zero field for the neat solid form. In the absence of EPR signals for 1-3, we show that heat-capacity measurements for one of the complexes (3) establish a geff value near 12, in agreement with the principal component of the ligand electric field gradient being coincident with the z axis.
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Direct Resonant Coupling of Al Surface Plasmon for Ultraviolet Photoluminescence Enhancement of ZnO Microrods.
ACS Appl Mater Interfaces
PUBLISHED: 10-02-2014
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More than 170-fold ultraviolet emission enhancement was obtained from the hexagonal ZnO microrods synthesized by a simple vapor-phase transport process and decorated by Al nanoparticles (NPs). Based on the stable and transient photoluminescence (PL) spectra of the ZnO microrods sputtered with Al NPs for different times, the underlying mechanism was deduced and can be attributed to the metal surface plasmon resonance (SPR) coupling with ZnO. Interestingly, with increasing of the sputtering time, the ratio of the band gap emission to the defect-related emission was increased from 0.1 to 42.7. Our results demonstrated that ZnO microrods decorated with Al NPs shed light on developing stable and high-efficiency excitonic optoelectronic devices such as light-emitting diodes and lasers.
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Immunoglobulin light chain amyloidosis is diagnosed late in patients with preexisting plasma cell dyscrasias.
Am. J. Hematol.
PUBLISHED: 09-02-2014
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AL amyloidosis (AL) is rare and frequently remains undiagnosed until organ function is compromised, even among patients with known pre-existing untreated plasma cell dyscrasias (PCD). We identified 168 patients with AL amyloidosis who had a prior untreated PCD. The earliest symptom or sign (s/s) was defined as the first symptom reported by the patient that could be attributed to organ dysfunction caused by AL. The interval from the time of development of s/s to the establishment of diagnosis of AL (Interval-SA) was calculated. PCD diagnosis preceded recorded onset of s/s in 75% (114/152) of patients, with a median interval-SA for this group of 10 months. PCD was diagnosed after s/s in 25% (38/152) of patients, with a median interval-SA of 20 months. Overall survival (OS) from diagnosis of AL was not different between the two groups. AL amyloidosis patients with an identified pre-existing PCD had less advanced cardiac disease at AL diagnosis when compared to a control group of AL patients without preidentified PCD. Long-term OS was not significantly superior among patients with a pre-identified PCD. In patients with "asymptomatic" PCD, symptoms and signs of AL amyloidosis should be solicited, since timely diagnosis is important in AL amyloidosis. Am. J. Hematol. 89:1051-1054, 2014. © 2014 Wiley Periodicals, Inc.
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Evidence of heterogeneity by race/ethnicity in genetic determinants of QT interval.
Epidemiology
PUBLISHED: 08-29-2014
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QT interval (QT) prolongation is an established risk factor for ventricular tachyarrhythmia and sudden cardiac death. Previous genome-wide association studies in populations of the European descent have identified multiple genetic loci that influence QT, but few have examined these loci in ethnically diverse populations.
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Comparing HbA1c, fasting and 2-h plasma glucose for screening for abnormal glucose regulation in patients undergoing coronary angiography.
Clin. Chem. Lab. Med.
PUBLISHED: 08-27-2014
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Abstract Background: We aimed to investigate the prevalence of undiagnosed abnormal glucose regulation (AGR, including diabetes and prediabetes) in patients undergoing coronary angiography (CAG) by using both glycated hemoglobin (HbA1c) and oral glucose tolerance test (OGTT) to screen, and to compare the performance of fasting plasma glucose (FPG), 2-h plasma glucose (2hPG), and HbA1c for screening for AGR. Methods: Eligible patients were adults without known diabetes who were admitted for CAG. Patients' glucose regulation status was defined by conducting HbA1c and OGTT 2-4 weeks after hospital discharge. The performance of FPG, 2hPG, and HbA1c for detecting AGR was evaluated using receiver operating characteristic (ROC) analysis. Results: A total of 689 subjects were included. According to OGTT, the prevalence rates of diabetes and prediabetes were 19.9% and 41.7%, respectively. The corresponding values were 28.0% and 60.4%, respectively, when HbA1c was adopted as a diagnostic criterion in addition to OGTT. For detecting diabetes, the area under the ROC curve (AUC) was higher for HbA1c than for FPG (0.87 vs. 0.80, p=0.005), but was not significantly different from that for 2hPG (0.87 vs. 0.88, p=0.58). For detecting AGR, the AUC was higher for HbA1c than for either FPG (0.94 vs. 0.74, p<0.001) or 2hPG (0.94 vs. 0.83, p<0.001). Conclusions: Using HbA1c and OGTT to screen, we reported an extremely high prevalence of previously undiagnosed AGR (28.0% diabetes and 60.4% prediabetes) in patients admitted for CAG. HbA1c may be adopted as an alternative to OGTT for screening for AGR in patients undergoing CAG.
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The role of biotin and oxamate in the carboxyltransferase reaction of pyruvate carboxylase.
Arch. Biochem. Biophys.
PUBLISHED: 08-23-2014
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Pyruvate carboxylase (PC) is a biotin-dependent enzyme that catalyzes the MgATP-dependent carboxylation of pyruvate to oxaloacetate, an important anaplerotic reaction in central metabolism. During catalysis, carboxybiotin is translocated to the carboxyltransferase domain where the carboxyl group is transferred to the acceptor substrate, pyruvate. Many studies on the carboxyltransferase domain of PC have demonstrated an enhanced oxaloacetate decarboxylation activity in the presence of oxamate and it has been shown that oxamate accepts a carboxyl group from carboxybiotin during oxaloacetate decarboxylation. The X-ray crystal structure of the carboxyltransferase domain from Rhizobium etli PC reveals that oxamate is positioned in the active site in an identical manner to the substrate, pyruvate, and kinetic data are consistent with the oxamate-stimulated decarboxylation of oxaloacetate proceeding through a simple ping-pong bi bi mechanism in the absence of the biotin carboxylase domain. Additionally, analysis of truncated PC enzymes indicates that the BCCP domain devoid of biotin does not contribute directly to the enzymatic reaction and conclusively demonstrates a biotin-independent oxaloacetate decarboxylation activity in PC. These findings advance the description of catalysis in PC and can be extended to the study of related biotin-dependent enzymes.
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Insulinoma in a Young Female Patient with Systemic Lupus Erythematosus: A Case Report.
Endocr Pract
PUBLISHED: 08-22-2014
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Objective: Fasting hypoglycemia may occur in subjects with systemic lupus erythematosus (SLE) when accompanied with insulin-binding antibodies or insulin receptor antibodies. However, insulinoma has not been reported in SLE subjects with hypoglycemia.Methods: We present a case report and review the relevant literature.Results: A 26-year-old female with underlying SLE experienced several episodes of neuropsychiatric symptoms in a fasting state. The steroid dosage was titrated up, but in vain. Timely imaging studies showed a pancreatic tumor, and insulinoma was proven by pathology. Hypoglycemia did not recur after surgery.Conclusion: Physicians should distinguish insulinoma from autoimmunity-mediated hypoglycemia in SLE patients with fasting hypoglycemia.
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Cold exposure inhibits hypothalamic Kiss-1 gene expression, serum leptin concentration, and delays reproductive development in male Brandt's vole (Lasiopodomys brandtii).
Int J Biometeorol
PUBLISHED: 08-22-2014
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Cold commonly affects growth and reproductive development in small mammals. Here, we test the hypothesis that low ambient temperature will affect growth and puberty onset, associated with altered hypothalamic Kiss-1 gene expression and serum leptin concentration in wild rodents. Male Brandt's voles (Lasiopodomys brandtii) were exposed to cold (4?±?1 °C) and warm (23?±?1 °C) conditions from the birth and sacrificed on different developmental stages (day 26, day 40, day 60, and day 90, respectively). Brandt's voles increased the thermogenic capacity of brown adipose tissue, mobilized body fat, decreased serum leptin levels, and delayed the reproductive development especially on day 40 in the cold condition. They increased food intake to compensate for the high energy demands in the cold. The hypothalamic Kiss-1 gene expression on day 26 was decreased, associated with lower wet testis mass and testis testosterone concentration on day 40, in the cold-exposed voles compared to that in the warm. Serum leptin was positively correlated with body fat, testis mass, and testosterone concentration. These data suggested that cold exposure inhibited hypothalamic Kiss-1 gene expression during the early stage of development, decreased serum leptin concentration, and delayed reproductive development in male Brandt's voles.
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Association of Cancer Susceptibility Variants with Risk of Multiple Primary Cancers: The Population Architecture using Genomics and Epidemiology Study.
Cancer Epidemiol. Biomarkers Prev.
PUBLISHED: 08-19-2014
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Multiple primary cancers account for approximately 16% of all incident cancers in the United States. Although genome-wide association studies (GWAS) have identified many common genetic variants associated with various cancer sites, no study has examined the association of these genetic variants with risk of multiple primary cancers (MPC).
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[Epidemiology of hand, foot, and mouth disease and genetic characterization of enterovirus A71: a survey from 2007 to 2012 in Linyi of Shandong Province, China].
Bing Du Xue Bao
PUBLISHED: 08-15-2014
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To investigate the epidemiology of hand, foot, and mouth disease (HFMD) and the genetic characteristics of enterovirus A71 (EV-A71) in Linyi of Shandong Province, China during 2007-2012. The number of reported HFMD cases were obtained from the National Notifiable Disease Reporting System (NNDRS) were analyzed by descriptive epidemiology method; the VP1 region of EV-A71 isolated from HFMD patients in Linyi was amplified and sequenced. Finally, the genetic variability and phylogenecity of VP1 sequences of EV-A71 were analyzed by MEGA 5.0. The results showed that HFMD incidence was reported in each year from 2007 to 2012 in Linyi, and the highest incidence and mortality were reported in 2009, when there were total 14697 cases and 9 of death. The reported incidence was 140.28/100000, and the mortality was 0.086/100000. The peak incidence usually occurred between April and July, and the summit occurred in May. Scattered children accounted for 77.37%-92.00% of all cases. The peak age was 2.5 years during 2007-2009 and 1.5 years during 2010-2012. A total of 1365 laboratory-confirmed HFMD cases were reported in the 6 consecutive years, accounting for 2.98% of the gross number. Among these reports, the ratio of EV-A71 was 44.18%, and the ratio of coxsackievirus A16 (CVA16) was 46.59%. All EV-A71 strains isolated in Linyi during 2007-2012 belonged to the C4a evolutionary branch of C4 genotype. In conclusion, HFMD outbreaks occurred every year in Linyi during 2007-2012. Incidence varied significantly among different counties. The peak incidence in each year lasted from April to July. Most of the patients were children under 3 years of age, and scattered children took the highest proportion. Co-circulation of EV-A71 and CVA16 was the major cause of HFMD in each year. Since the first report of HFMD prevalence caused by EV-A71 (C4a) in 2007, the virus has been prevalent continuously in Linyi for 6 years.
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Synthesis, structure, and magnetic and electrochemical properties of quasi-linear and linear iron(I), cobalt(I), and nickel(I) amido complexes.
Inorg Chem
PUBLISHED: 08-13-2014
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Three potassium crown ether salts, [K(Et2O)2(18-crown-6)][Fe{N(SiMe3)Dipp}2] (1a; Dipp = C6H3-2,6-Pr(i)2), [K(18-crown-6)][Fe{N(SiMe3)Dipp}2]·0.5PhMe (1b), and [K(18-crown-6)][M{N(SiMe3)Dipp}2] (M = Co, 2; M = Ni, 3), of the two-coordinate linear or near-linear bis-amido monoanions [M{N(SiMe3)Dipp}2](-) (M = Fe, Co, Ni) were synthesized by one-electron reduction of the neutral precursors M{N(SiMe3)Dipp}2 with KC8 in the presence of 18-crown-6. They were characterized by X-ray crystallography, UV-vis spectroscopy, cyclic voltammetry, and magnetic measurements. The anions feature lengthened M-N bonds in comparison with their neutral precursors, with slightly bent coordination (N-Fe-N = ca. 172°) for the iron(I) complex, but linear coordination for the cobalt(I) and nickel(I) complexes. Fits of the temperature dependence of ?MT of 1 and 2 reveal that the iron(I) and cobalt(I) complexes have large negative D zero-field splittings and a substantial orbital contribution to their magnetic moments with L = 2, whereas the nickel(I) complex has at most a small orbital contribution to its magnetic moment. The magnetic results have been used to propose an ordering of the 3d orbitals in each of the complexes.
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The CELSR1 polymorphisms rs6007897 and rs4044210 are associated with ischaemic stroke in Chinese Han population.
Ann. Hum. Biol.
PUBLISHED: 08-13-2014
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Abstract Background: Recently, CELSR1 was identified by genome-wide association studies (GWAS) as a susceptibility gene for ischaemic stroke (IS) in Japanese individuals. Aim: The goal was to examine whether CELSR1 variants are associated with IS in the Chinese Han population. Subjects and methods: This study genotyped two single nucleotide polymorphisms (SNPs) of CELSR1, rs6007897 and rs4044210, in a Chinese sample of 569 IS cases and 581 controls and assessed their genotype and allele associations with IS. Results: The results showed that rs6007897 and rs4044210 variants of CELSR1 were significantly (p?
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Perinatal exposure to bisphenol A exacerbates nonalcoholic steatohepatitis-like phenotype in male rat offspring fed on a high-fat diet.
J. Endocrinol.
PUBLISHED: 08-13-2014
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Bisphenol A (BPA) is one of the environmental endocrine disrupting chemicals, which is present ubiquitously in daily life. Accumulating evidence indicates that exposure to BPA contributes to metabolic syndrome. In this study, we examined whether perinatal exposure to BPA predisposed offspring to fatty liver disease: the hepatic manifestation of metabolic syndrome. Wistar rats were exposed to 50 ?g/kg per day BPA or corn oil throughout gestation and lactation by oral gavage. Offspring were fed a standard chow diet (SD) or a high-fat diet (HFD) after weaning. Effects of BPA were assessed by examination of hepatic morphology, biochemical analysis, and the hepatic expression of genes and/or proteins involved in lipogenesis, fatty acid oxidation, gluconeogenesis, insulin signaling, inflammation, and fibrosis. On a SD, the offspring of rats exposed to BPA exhibited moderate hepatic steatosis and altered expression of insulin signaling elements in the liver, but with normal liver function. On a HFD, the offspring of rats exposed to BPA showed a nonalcoholic steatohepatitis-like phenotype, characterized by extensive accumulation of lipids, large lipid droplets, profound ballooning degeneration, impaired liver function, increased inflammation, and even mild fibrosis in the liver. Perinatal exposure to BPA worsened the hepatic damage caused by the HFD in the rat offspring. The additive effects of BPA correlated with higher levels of hepatic oxidative stress. Collectively, exposure to BPA may be a new risk factor for the development of fatty liver disease and further studies should assess whether this finding is also relevant to the human population.
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Scalable holey graphene synthesis and dense electrode fabrication toward high-performance ultracapacitors.
ACS Nano
PUBLISHED: 08-05-2014
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Graphene has attracted a lot of attention for ultracapacitor electrodes because of its high electrical conductivity, high surface area, and superb chemical stability. However, poor volumetric capacitive performance of typical graphene-based electrodes has hindered their practical applications because of the extremely low density. Herein we report a scalable synthesis method of holey graphene (h-Graphene) in a single step without using any catalysts or special chemicals. The film made of the as-synthesized h-Graphene exhibited relatively strong mechanical strength, 2D hole morphology, high density, and facile processability. This scalable one-step synthesis method for h-Graphene is time-efficient, cost-efficient, environmentally friendly, and generally applicable to other two-dimensional materials. The ultracapacitor electrodes based on the h-Graphene show a remarkably improved volumetric capacitance with about 700% increase compared to that of regular graphene electrodes. Modeling on individual h-Graphene was carried out to understand the excellent processability and improved ultracapacitor performance.
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Performance evaluation of time-aware enhanced software defined networking (TeSDN) for elastic data center optical interconnection.
Opt Express
PUBLISHED: 08-05-2014
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Data center interconnection with elastic optical networks is a promising scenario to meet the high burstiness and high-bandwidth requirements of data center services. We previously implemented enhanced software defined networking over elastic optical network for data center application [Opt. Express 21, 26990 (2013)]. On the basis of it, this study extends to consider the time-aware data center service scheduling with elastic service time and service bandwidth according to the various time sensitivity requirements. A novel time-aware enhanced software defined networking (TeSDN) architecture for elastic data center optical interconnection has been proposed in this paper, by introducing a time-aware resources scheduling (TaRS) scheme. The TeSDN can accommodate the data center services with required QoS considering the time dimensionality, and enhance cross stratum optimization of application and elastic optical network stratums resources based on spectrum elasticity, application elasticity and time elasticity. The overall feasibility and efficiency of the proposed architecture is experimentally verified on our OpenFlow-based testbed. The performance of TaRS scheme under heavy traffic load scenario is also quantitatively evaluated based on TeSDN architecture in terms of blocking probability and resource occupation rate.
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Rapid in situ detection of ultratrace 2,4-dinitrotoluene solids by a sandwiched paper-like electrochemical sensor.
Anal. Chem.
PUBLISHED: 08-05-2014
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This work reported the rapid in situ detection of ultratrace 2,4-dinitrotoluene (DNT) solids on various substrates by a sandwiched paper-like electrochemical sensor. The sensor, prepared by a simple electroless deposition method without using special instruments, possessed a unique thin-film structure of an insulated polyvinylidene fluoride (PVDF) membrane in between two gold (Au) conducting layers. The resulting gold-PVDF sandwich (GPVDFS) array exhibited excellent flexibility, porosity and electrochemical performance as a highly integrated dual-electrode sensor platform. The infiltration of nonvolatile ionic liquid (IL) electrolytes containing ferrocene (Fc) into the GPVDFS array produced a paper-like electrochemical sensor, which can directly detect ultratrace DNT solids on various substrate surfaces (e.g., plant leaves, gloves and metal knives) with detection limit as low as 0.33 ng/mm(2). The critical role of Fc in the detection of DNT at this dual-electrode sensor was explored. The compensating electrochemical oxidation of Fc at the counter/reference electrode was found to be essential to the reduction of DNT at the working electrode when IL electrolytes were employed. The present work thus demonstrated the promising applications of paper-based porous electrode arrays in developing IL-based electrochemical sensors for the in situ detection of analyte solids in complicated environments.
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Caveolin-1 mediates chemoresistance in breast cancer stem cells via ?-catenin/ABCG2 signaling pathway.
Carcinogenesis
PUBLISHED: 08-01-2014
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Accumulating evidence has suggested that cancer stem cells (CSCs) are at the root of drug resistance, and recent studies have indicated that caveolin-1, a membrane transporter protein, is involved in the regulation of cancer chemoresistance and stem cell signaling. However, the current understanding of the role of caveolin-1 in breast cancer development remains controversial. Herein, we demonstrate that caveolin-1 expression was upregulated after breast cancer chemotherapy in vitro and in vivo, accompanied by co-overexpression of ?-catenin and ATP-binding cassette subfamily G member 2 (ABCG2) signaling. Additionally, breast CSCs were enriched for caveolin-1 expression. Caveolin-1 silencing sensitized breast CSCs by limiting their self-renewal ability but promoting the differentiation process. ?-catenin silencing prevented the enhanced chemoresistance of CSCs induced by caveolin-1 overexpression, indicating that ?-catenin is an essential molecule responsible for caveolin-1-mediated action. Further mechanistic investigation revealed that caveolin-1 silencing could downregulate the ?-catenin/ABCG2 pathway through glycogen synthase kinase 3 beta activation and Akt inhibition, resulting in increased ?-catenin phosphorylation and proteasomal degradation. Clinical investigation also revealed a close correlation between caveolin-1 and ?-catenin/ABCG2 signaling in breast cancer samples. Notably, caveolin-1 was highly elevated in triple-negative breast cancer, and caveolin-1 silencing significantly impaired the tumorigenicity and chemoresistance of breast CSCs in in vivo models. Overall, our study not only highlights the role of caveolin-1 in mediating the chemoresistance of breast CSCs via ?-catenin/ABCG2 regulation but also provides novel approaches for future therapies targeting CSCs.
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Reliability and reproducibility of landmarks on three-dimensional soft-tissue cephalometrics using different placement methods.
Plast. Reconstr. Surg.
PUBLISHED: 07-17-2014
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Affixing markers on the face in vivo with an optical surface imaging system and placing landmarks on a computed tomographic reconstructive facial model represent two helpful approaches prevailing in three-dimensional cephalometric analysis of facial aesthetics. In this study, the authors determine the suitability of these methods for soft-tissue evaluation along with the reproducibility and reliability of landmark placement.
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MicroRNA-25 regulates chemoresistance-associated autophagy in breast cancer cells, a process modulated by the natural autophagy inducer isoliquiritigenin.
Oncotarget
PUBLISHED: 07-16-2014
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Recent findings have revealed that dysregulated miRNAs contribute significantly to autophagy and chemoresistance. Pharmacologically targeting autophagy-related miRNAs is a novel strategy to reverse drug resistance. Here, we report a novel function of isoliquiritigenin (ISL) as a natural inhibitor of autophagy-related miR-25 in killing drug-resistant breast cancer cells. ISL induced chemosensitization, cell cycle arrest and autophagy, but not apoptosis, in MCF-7/ADR cells. ISL also promoted the degradation of the ATP-binding cassette (ABC) protein ABCG2 primarily via the autophagy-lysosome pathway. More importantly, miRNA 3.0 array experiments identified miR-25 as the main target of ISL in triggering autophagy flux. A mechanistic study validated that miR-25 inhibition led to autophagic cell death by directly increasing ULK1 expression, an early regulator in the autophagy induction phase. miR-25 overexpression was demonstrated to block ISL-induced autophagy and chemosensitization. Subsequent in vivo experiments showed that ISL had chemosensitizing potency, as revealed by an increase in LC3-II staining, the downregulation of ABCG2, a reduction in miR-25 expression and the activation of the miR-25 target ULK1. Overall, our results not only indicate that ISL acts as a natural autophagy inducer to increase breast cancer chemosensitivity, but also reveal that miR-25 functions as a novel regulator of autophagy by targeting ULK1.
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TAT-mediated delivery of neuroglobin attenuates apoptosis induced by oxygen-glucose deprivation via the Jak2/Stat3 pathway in vitro.
Neurol. Res.
PUBLISHED: 07-16-2014
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Objectives: Neuroglobin (Ngb), an identified globin in vertebrate brain, is a potential novel protective protein against brain ischemia. In our previous study, the human immunodeficiency virus trans-activator of transcription (TAT) protein transduction domain successfully delivered exogenous Ngb into neurons in the mouse, and protected the brain from cerebral ischemia-induced apoptosis. The aim of this study is to investigate the role of TAT-Ngb in attenuating oxygen-glucose deprivation (OGD) induced apoptosis and to explore the possible mechanism. Methods: Nerve growth factor (NGF)-induced PC12 cells were divided into (1) the control group, (2) the OGD group (just OGD), (3) the Ngb treatment group (OGD and Ngb treatment), and (4) the TAT-Ngb treatment group (OGD and TAT-Ngb treatment). Cell viability and apoptosis were assessed by the MTT assay and the AnnexinV/propidium iodide (PI) staining, respectively. The mitochondrial transmembrane potential was measured by JC-1 staining. Caspase-3, Bcl-2, Bax, Stat3, Jak2, and Akt were determined by western blot analysis. Results: Trans-activator of transcription effectively delivered Ngb into NGF-induced PC12 cells. Neuroglobin-mediated neuroprotection rescued cultured cells from OGD. We also confirmed previous findings that TAT-Ngb inhibited mitochondrial apoptosis following OGD. Inhibition of apoptosis by Ac-DEVD-CHO showed that caspase-3 was a crucial factor in OGD-induced apoptosis cascades. AG490, a specific Jak2 inhibitor, attenuated the protective effects of TAT-Ngb. The TAT-Ngb promoted expression of the anti-apoptotic protein Bcl-2 through the Jak2/Stat3 signal pathway, and inhibited apoptosis by blocking caspase-3 activation, while the Jak-Akt-Stat3 signal network was not involved. Conclusion: Our results demonstrate that TAT-Ngb can protect neuron-like cells against OGD-induced apoptosis by activating the Jak2/Stat3 pathway.
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Beneficial effect of quercetin on cholestatic liver injury.
J. Nutr. Biochem.
PUBLISHED: 07-15-2014
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Bile duct obstruction and subsequent cholestasis are associated with hepatocellular injury, cholangiocyte proliferation, stellate cell activation, Kupffer cell activation, oxidative stress, inflammation and fibrosis. Flavonoids have been shown to confer beneficial health effects, including hepatoprotection. However, the molecular mechanism of flavonoid-mediated hepatoprotection is incompletely understood. In this study, we report the protective effect of quercetin on cholestatic liver injury. Cholestasis was produced by bile duct ligation (BDL) in male Sprague-Dawley rats for 3weeks. Daily oral administration of quercetin was started 1week before injury and lasted for 4weeks. In comparison with the control group, the BDL group showed liver injury, as evidenced by histological changes, and elevation in serum biochemicals, ductular reaction, fibrosis, inflammation and oxidative stress. These pathophysiological changes were attenuated by daily quercetin supplementation. Quercetin alleviated BDL-induced transforming growth factor beta-1 (TGF-?1), interleukin-1 beta, connective tissue growth factor and collagen expression. The antifibrotic effect of quercetin was accompanied by reductions in ?-smooth muscle actin-positive matrix-producing cells and Smad 2/3 activity critical to the fibrogenic potential of TGF-?1. Quercetin also attenuated BDL-induced oxidative stress, leukocyte accumulation, nuclear factor (NF)-?B activation and proinflammatory cytokine production. Further studies demonstrated an inhibitory effect of quercetin on MyD88 and TGF-?-activated kinase-1 critical for linking toll-like receptor (TLR) and NF-?B. Taken together, the hepatoprotective, anti-inflammatory and antifibrotic effects of quercetin seem to be multifactorial. The beneficial effects of daily quercetin supplementation are associated with antioxidative and anti-inflammatory potential as well as down-regulation of NF-?B and TGF-?/Smad signaling, probably via interference with TLR signaling.
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A linearity-enhanced time-domain CMOS thermostat with process-variation calibration.
Sensors (Basel)
PUBLISHED: 07-13-2014
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This study proposes a linearity-enhanced time-domain complementary metal-oxide semiconductor (CMOS) thermostat with process-variation calibration for improving the accuracy, expanding the operating temperature range, and reducing test costs. For sensing temperatures in the time domain, the large characteristic curve of a CMOS inverter markedly affects the accuracy, particularly when the operating temperature range is increased. To enhance the on-chip linearity, this study proposes a novel temperature-sensing cell comprising a simple buffer and a buffer with a thermal-compensation circuit to achieve a linearised delay. Thus, a linearity-enhanced oscillator consisting of these cells can generate an oscillation period with high linearity. To achieve one-point calibration support, an adjustable-gain time stretcher and calibration circuit were adopted for the process-variation calibration. The programmable temperature set point was determined using a reference clock and a second (identical) adjustable-gain time stretcher. A delay-time comparator with a built-in customised hysteresis circuit was used to perform a time comparison to obtain an appropriate response. Based on the proposed design, a thermostat with a small area of 0.067 mm2 was fabricated using a TSMC 0.35-?m 2P4M CMOS process, and a robust resolution of 0.05 °C and dissipation of 25 ?W were achieved at a sample rate of 10 samples/s. An inaccuracy of -0.35 °C to 1.35 °C was achieved after one-point calibration at temperatures ranging from -40 °C to 120 °C. Compared with existing thermostats, the proposed thermostat substantially improves the circuit area, accuracy, operating temperature range, and test costs.
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Curvature-correction-based time-domain CMOS smart temperature sensor with an inaccuracy of -0.8?°C-1.2?°C after one-point calibration from -40?°C to 120?°C.
Rev Sci Instrum
PUBLISHED: 07-03-2014
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This paper proposes a time-domain CMOS smart temperature sensor featuring on-chip curvature correction and one-point calibration support for thermal management systems. Time-domain inverter-based temperature sensors, which exhibit the advantages of low power and low cost, have been proposed for on-chip thermal monitoring. However, the curvature is large for the thermal transfer curve, which substantially affects the accuracy as the temperature range increases. Another problem is that the inverter is sensitive to process variations, resulting in difficulty for the sensors to achieve an acceptable accuracy for one-point calibration. To overcome these two problems, a temperature-dependent oscillator with curvature correction is proposed to increase the linearity of the oscillatory width, thereby resolving the drawback caused by a costly off-chip second-order master curve fitting. For one-point calibration support, an adjustable-gain time amplifier was adopted to eliminate the effect of process variations, with the assistance of a calibration circuit. The proposed circuit occupied a small area of 0.073 mm(2) and was fabricated in a TSMC CMOS 0.35-?m 2P4M digital process. The linearization of the oscillator and the effect cancellation of process variations enabled the sensor, which featured a fixed resolution of 0.049?°C/LSB, to achieve an optimal inaccuracy of -0.8?°C to 1.2?°C after one-point calibration of 12 test chips from -40?°C to 120?°C. The power consumption was 35 ?W at a sample rate of 10 samples/s.
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Elevated monoclonal and polyclonal serum immunoglobulin free light chain as prognostic factors in B- and T-cell non-Hodgkin lymphoma.
Am. J. Hematol.
PUBLISHED: 07-01-2014
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The serum immunoglobulin free light chain (FLC) assay quantitates free kappa (?) and lambda (?) light chains. FLC elevations in patients with diffuse large B-cell lymphoma (DLBCL), Hodgkin lymphoma (HL), and chronic lymphocytic leukemia (CLL) are associated with an inferior survival. These increases in FLC can be monoclonal (as in myeloma) or polyclonal. The goal was to estimate the frequency of these elevations within distinct types of B-cell and T-cell non-Hodgkin lymphoma (NHL) and whether the FLC measurements are associated with event-free survival (EFS). We studied serum for FLC abnormalities using normal laboratory reference ranges to define an elevated ? or ? FLC. Elevations were further classified as polyclonal or monoclonal. Four hundred ninety-two patients were studied: 453 B-cell and 34 T-cell NHL patients. Twenty-nine % (142/453) of patients had an elevated FLC of which 10% were monoclonal elevations. Within B-cell NHL, FLC abnormalities were most common in lymphoplasmacytic (79%), mantle cell (68%), and lymphomas of mucosa associated lymphoid tissue (31%); they were least common in follicular (15%). The hazard ratio (HR) for EFS in all patients was 1.41 (95% CI; 1.11-1.81); in all B-cell NHL the HR was 1.44 (95% CI 1.11-1.96); in all T-cell NHL the HR was 1.17 (95% CI 0.55-2.49). FLC abnormalities predicted an inferior OS (HR?=?2.75, 95% CI: 1.93-3.90, P?
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Graphene surface plasmon induced optical field confinement and lasing enhancement in ZnO whispering-gallery microcavity.
ACS Appl Mater Interfaces
PUBLISHED: 06-27-2014
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Fundamental physics under the surface plasmon (SP) of graphene and the functional application beyond ultraviolet (UV) lasing of ZnO are both fascinating research areas. Herein, the optical field confinement induced by graphene SP was simulated theoretically in a graphene-coated ZnO microrod, which acted as a whispering-gallery microcavity for lasing resonance. Distinct optical field confinement and photoluminescence (PL) enhancement were observed experimentally. Stable and transient spectra were employed to analyze the PL enhancement and the coupling dynamics between graphene SP and ZnO interband emission. As a functional application, the graphene-coated ZnO microcavities presented the obviously improved whispering-gallery mode (WGM) lasing performance. These results would be valuable for designing novel optical and photoelectronic devices based on SP coupling in graphene-semiconductor hybrid materials.
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Serum total bilirubin concentrations are inversely associated with total white blood cell counts in an adult population.
Ann. Clin. Biochem.
PUBLISHED: 06-12-2014
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Several studies have shown that serum bilirubin has a protective effect against cardiovascular disease and that inflammation plays an important role in its pathogenesis. This cross-sectional study investigated whether there was an association between blood total white blood cell count, a simple indicator of inflammation, and serum total bilirubin concentration in a cohort of an adult population in Taiwan.
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Reduced health-related quality of life in body constitutions of yin-xu, and yang-xu, stasis in patients with type 2 diabetes: taichung diabetic body constitution study.
Evid Based Complement Alternat Med
PUBLISHED: 06-09-2014
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Aim. To evaluate how health-related quality of life (HRQOL) and traditional Chinese medicine (TCM) constitutions of Yin-Xu, Yang-Xu, and Stasis are related in type 2 diabetes patients. Method. Seven hundred and five subjects were recruited in 2010 for this study from a Diabetes Shared Care Network in Taiwan. Generic and disease-specific HRQOL were assessed by the short form 36 (SF-36) and the diabetes impact measurement scale (DIMS). Constitutions of Yin-Xu, Yang-Xu, and Stasis were then assessed by the body constitution questionnaire (BCQ), a questionnaire consisting of 44 items that evaluate the physiological state based on subjective symptoms and signs. Results. Estimated effects of the Ying-Xu and Stasis on all scales of the SF-36 were significantly negative, while estimated effects of the Yang-Xu on all scales (except for SF, RE, MH, and MCS) were significantly negative. For DIMS, the estimated effects of the Ying-Xu and Stasis on all scales were significantly negative except for Stasis on well-being, while Yang-Xu has a significantly negative effect only on symptoms. Conclusions. This study demonstrates that TCM constitutions of Yin-Xu, Yang-Xu, and Stasis are closely related to a reduction in HRQOL. These findings support the need for further research into the impact of intervention for TCM constitutions on HRQOL in patients with type 2 diabetes.
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Effect of processing conditions on the organosulfides of shallot (Allium cepa L. Aggregatum group).
J. Agric. Food Chem.
PUBLISHED: 06-02-2014
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There is a growing account of the health benefits of H2S as an endogenous cell-signaling molecule. H2S from organic polysulfides, in particular, is increasingly gaining attention for their beneficial effects to cardiovascular health. Here, we studied shallot as a potential dietary source of organic polysulfides and examined the effects of processing conditions on its polysulfide profiles. Boiling, autoclaving, and freeze-drying were tested on whole and crushed shallot bulbs, analyzing their effect on the yield of organosulfides. Seventeen organosulfides, including disulfides, trisulfides, and cyclic polysulfides, were identified. Significant differences in the quantitative and qualitative profiles of organosulfides in the hydrodistilled and solvent extracted oils were observed. Freeze-drying retained the majority of the organosulfides, but the whole-autoclaved and whole-boiled shallots lost more than 95% of their organic polysulfides. Crushed-boiled and crushed-autoclaved shallot lost 76-80% of their organosulfides, likely due to the thermal sensitivity of these compounds. The organosulfide profiles are sensitive to the pH values of the processing media. In general, disulfides increased at basic pH (pH 9.0) while trisulfides and cyclic organosulfides are much higher at the acidic to neutral pH values (pH 3.0-5.0). Our results provide important information on the effects of processing conditions that are relevant for optimizing extraction of organosulfides from shallot for further studies evaluating their H2S-releasing activity.
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Periodontitis exposure within one year before anti-diabetic treatment and the risk of rheumatoid arthritis in diabetes mellitus patients: a population-based cohort study.
Rev Bras Reumatol
PUBLISHED: 06-01-2014
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To examine whether a history of periodontitis (PD) before anti-diabetic treatment is associated with risk of rheumatoid arthritis (RA) development in newly-treated diabetes mellitus (DM) patients.
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[Application of three-dimensional printing technique in repair and reconstruction of maxillofacial bone defect].
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi
PUBLISHED: 05-22-2014
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To explore the application of three-dimensional (3-D) printing technique in repair and reconstruction of maxillofacial bone defect.
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Weight loss reduces serum monocyte chemoattractant protein-1 concentrations in association with improvements in renal injury in obese men with metabolic syndrome.
Clin. Chem. Lab. Med.
PUBLISHED: 05-01-2014
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Abstract Background: Monocyte chemoattractant protein-1 (MCP-1) is involved in obesity-related renal injury. The aim of the present study was to examine the effects of weight loss on changes in MCP-1 and markers of renal injury, specifically serum cystatin C (S-CysC) and urinary N-acetyl glucosaminidase (UNAG), in obese people. Methods: In this prospective study, 40 obese men with metabolic syndrome (MetS) participated in a 3-month dietary and exercise intervention. Twenty-eight subjects completed the study with a ?5% weight loss. Circulating MCP-1, S-CysC and UNAG to creatinine ratio (UNCR) were determined before and after the weight loss program. Results: Obesity-associated components of MetS demonstrated significant improvements after the weight loss program. In addition, at baseline, circulating MCP-1 concentrations were positively correlated with UNCR and S-CysC levels. After weight loss, blood MCP-1 and UNCR levels were significantly decreased, but S-CysC was not affected. Using multiple linear regression analysis, there was a significant relationship between changes in UNCR and MCP-1 after adjusting for other potential confounding factors. Conclusions: Weight loss may improve renal tubular injury by ameliorating obesity-related inflammation in obese men with MetS.
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Endothelial cell injury and dysfunction induced by silver nanoparticles through oxidative stress via IKK/NF-?B pathways.
Biomaterials
PUBLISHED: 04-02-2014
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Epidemiological studies have indicated that particulate matter (PM) exposure is most likely relevant to atherosclerosis. Endothelial cell injury and dysfunction are considered the early events in the initiation of atherosclerosis. Silver nanoparticles (AgNPs), with a smaller size and higher reactive activity, may induce much higher toxicity to endothelial cells compared with PM. However, few studies have been performed to determine the effect of AgNPs on endothelial cells. In the present study, human umbilical vein endothelial cells (HUVECs) were chosen as model cells to systematically explore the toxicity of AgNPs to endothelial cells. The obtained results indicated that exposure to AgNPs could inhibit proliferation, damage the cell membrane and seriously induce apoptosis. Simultaneously, the inflammatory cytokines, adhesion molecules, and chemokines of HUVECs were clearly up-regulated, which resulted in the adhesion of many monocytes to endothelial cells. More importantly, we found that dysfunctions of endothelial cells could be ascribed to the activation of NF-?B pathways. Furthermore, an oxidation inhibitor, N-acetyl-l-cysteine (NAC), effectively antagonized all of the AgNPs-induced responses, which indicated the key role of ROS production during the exposure of AgNPs in the toxicity of endothelial cells. In summary, our results clearly demonstrated that AgNPs could induce the injury and dysfunction of HUVECs through the activation of IKK/NF-?B, which is associated with oxidative stress, suggesting that exposure to AgNPs may be a potential hazardous factor for early atherosclerosis.
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Protective effects of rutin on liver injury induced by biliary obstruction in rats.
Free Radic. Biol. Med.
PUBLISHED: 02-21-2014
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Rutin has been shown to possess beneficial health effects, including hepatoprotection. However, to date, it has not been demonstrated to have a hepatoprotective effect against cholestatic liver injury. This is the first report to show a protective effect of rutin on cholestatic liver injury. Cholestasis was produced by bile duct ligation (BDL) in male Sprague-Dawley rats for 3 weeks. Daily oral administration of rutin was started 1 week before injury and was maintained for 4 weeks. In comparison with the control group, the BDL group showed liver injury as evidenced by histological changes and elevation in serum biochemicals, ductular reaction, fibrosis, inflammation, and oxidative stress. These pathophysiological changes were attenuated by rutin supplementation. Rutin alleviated BDL-induced transforming growth factor ?1 (TGF-?1), interleukin-1?, connective tissue growth factor, and collagen expression. The antifibrotic effect of rutin was accompanied by reductions in ?-smooth muscle actin-positive matrix-producing cells and Smad2/3 activity critical to the fibrogenic potential of TGF-?1. Rutin attenuated BDL-induced oxidative stress, leukocyte accumulation, NF-?B activation, and proinflammatory cytokine production. Further studies demonstrated an inhibitory effect of rutin on the redox-sensitive intracellular signaling molecule extracellular signal-regulated kinase (ERK). Rutin also attenuated BDL-induced reduction in NF-E2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and AMP-activated protein kinase (AMPK). Taken together, the beneficial effects of rutin were shown to be associated with antioxidative and anti-inflammatory effects as well as the downregulation of NF-?B and TGF-?/Smad signaling, probably via interference of ERK activation and/or enhancement of Nrf2, HO-1, and AMPK activity.
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N?-carboxymethyllysine-mediated endoplasmic reticulum stress promotes endothelial cell injury through Nox4/MKP-3 interaction.
Free Radic. Biol. Med.
PUBLISHED: 02-15-2014
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N(?)-carboxymethyllysine (CML) is an important driver of diabetic vascular complications and endothelial cell dysfunction. However, how CML dictates specific cellular responses and the roles of protein tyrosine phosphatases and ERK phosphorylation remain unclear. We examined whether endoplasmic reticulum (ER) localization of MAPK phosphatase-3 (MKP-3) is critical in regulating ERK inactivation and promoting NADPH oxidase-4 (Nox4) activation in CML-induced endothelial cell injury. We demonstrated that serum CML levels were significantly increased in type 2 diabetes patients and diabetic animals. CML induced ER stress and apoptosis, reduced ERK activation, and increased MKP-3 protein activity in HUVECs and SVECs. MKP-3 siRNA transfection, but not that of MKP-1 or MKP-2, abolished the effects of CML on HUVECs. Nox4-mediated activation of MKP-3 regulated the switch to ERK dephosphorylation. CML also increased the integration of MKP-3 with ERK, which was blocked by silencing MKP-3. Exposure of antioxidants abolished CML-increased MKP-3 activity and protein expression. Furthermore, immunohistochemical staining of both MKP-3 and CML was increased, but phospho-ERK staining was decreased in the aortic endothelium of streptozotocin-induced and high-fat diet-induced diabetic mice. Our results indicate that an MKP-3 pathway might regulate ERK dephosphorylation through Nox4 during CML-triggered endothelial cell dysfunction/injury, suggesting that therapeutic strategies targeting the Nox4/MKP-3 interaction or MKP-3 activation may have clinical implications for diabetic vascular complications.
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Brain-derived neurotrophic factor, but not body weight, correlated with a reduction in depression scale scores in men with metabolic syndrome: a prospective weight-reduction study.
Diabetol Metab Syndr
PUBLISHED: 02-11-2014
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Obesity, a critical component of metabolic syndrome (MetS), is associated with depression. Deficiency of brain-derived neurotrophic factor (BDNF) is involved in the mechanism of depression. We hypothesized that weight reduction would improve depressive symptoms via increasing BDNF levels in obese men.
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Contribution of bimodal hearing to lexical tone normalization in Mandarin-speaking cochlear implant users.
Hear. Res.
PUBLISHED: 02-09-2014
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Native Mandarin normal-hearing (NH) listeners can easily perceive lexical tones even under conditions of great voice pitch variations across speakers by using the pitch contrast between context and target stimuli. It is however unclear whether cochlear implant (CI) users with limited access to pitch cues can make similar use of context pitch cues for tone normalization. In this study, native Mandarin NH listeners and pre-lingually deafened unilaterally implanted CI users were asked to recognize a series of Mandarin tones varying from Tone 1 (high-flat) to Tone 2 (mid-rising) with or without a preceding sentence context. Most of the CI subjects used a hearing aid (HA) in the non-implanted ear (i.e., bimodal users) and were tested both with CI alone and CI + HA. In the test without context, typical S-shaped tone recognition functions were observed for most CI subjects and the function slopes and perceptual boundaries were similar with either CI alone or CI + HA. Compared to NH subjects, CI subjects were less sensitive to the pitch changes in target tones. In the test with context, NH subjects had more (resp. fewer) Tone-2 responses in a context with high (resp. low) fundamental frequencies, known as the contrastive context effect. For CI subjects, a similar contrastive context effect was found statistically significant for tone recognition with CI + HA but not with CI alone. The results suggest that the pitch cues from CIs may not be sufficient to consistently support the pitch contrast processing for tone normalization. The additional pitch cues from aided residual acoustic hearing can however provide CI users with a similar tone normalization capability as NH listeners.
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A clinical pathway for total shoulder arthroplasty-a pilot study.
HSS J
PUBLISHED: 01-31-2014
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Appropriate pain management after total shoulder arthroplasty (TSA) facilitates rehabilitation and may improve clinical outcomes.
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Association between Kawasaki disease and autism: a population-based study in Taiwan.
Int J Environ Res Public Health
PUBLISHED: 01-30-2014
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The association between Kawasaki disease and autism has rarely been studied in Asian populations. By using a nationwide Taiwanese population-based claims database, we tested the hypothesis that Kawasaki disease may increase the risk of autism in Taiwan.
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Sustainable deforestation evaluation model and system dynamics analysis.
ScientificWorldJournal
PUBLISHED: 01-28-2014
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The current study used the improved fuzzy analytic hierarchy process to construct a sustainable deforestation development evaluation system and evaluation model, which has refined a diversified system to evaluate the theory of sustainable deforestation development. Leveraging the visual image of the system dynamics causal and power flow diagram, we illustrated here that sustainable forestry development is a complex system that encompasses the interaction and dynamic development of ecology, economy, and society and has reflected the time dynamic effect of sustainable forestry development from the three combined effects. We compared experimental programs to prove the direct and indirect impacts of the ecological, economic, and social effects of the corresponding deforest techniques and fully reflected the importance of developing scientific and rational ecological harvesting and transportation technologies. Experimental and theoretical results illustrated that light cableway skidding is an ecoskidding method that is beneficial for the sustainable development of resources, the environment, the economy, and society and forecasted the broad potential applications of light cableway skidding in timber production technology. Furthermore, we discussed the sustainable development countermeasures of forest ecosystems from the aspects of causality, interaction, and harmony.
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Increased risk of Parkinson's disease in patients with end-stage renal disease: a retrospective cohort study.
Neuroepidemiology
PUBLISHED: 01-20-2014
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Studies on dyskinesia and Parkinson's syndrome associated with chronic kidney disease or end-stage renal disease (ESRD) have been mainly limited to case reports or case series studies. This population-based study investigated the risk of Parkinson's disease in patients with ESRD.
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Activation of hepatic inflammatory pathways by catecholamines is associated with hepatic insulin resistance in male ischemic stroke rats.
Endocrinology
PUBLISHED: 01-17-2014
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Patients who experience acute ischemic stroke may develop hyperglycemia, even in the absence of diabetes. In the current study we determined the effects of acute stroke on hepatic insulin signaling, TNF-? expression, endoplasmic reticulum (ER) stress, the activities of c-Jun N-terminal kinase (JNK), inhibitor ?B kinase ? (IKK-?), and nuclear factor-?B (NF-?B) pathways. Rats with cerebral ischemia developed higher blood glucose, and insulin levels, and insulin resistance index, as well as hepatic gluconeogenic enzyme expression compared with the sham-treated group. The hepatic TNF-? mRNA and protein levels were elevated in stroke rats in association with increased ER stress, phosphorylation of JNK1/2 and IKK-? proteins, I?B/NF-?B signaling, and phosphorylation of insulin receptor-1 (IRS-1) at serine residue. The basal and insulin-stimulated tyrosine phosphorylation of IRS-1 and AKT proteins was reduced. In addition, acute stroke increased circulating catecholamines in association with hepatic adrenergic signaling activation. After administration of a nonselective ?-adrenergic receptor blocker (propranolol) before induction of cerebral ischemic injury, hepatic adrenergic transduction, TNF-? expression, ER stress, and the activation of the JNK1/2, IKK-?, and NF-?B pathways, and serine phosphorylation of IRS-1 were all attenuated. In contrast, the phosphorylated IRS-1 at tyrosine site and AKT levels were partially restored with improved poststroke hyperglycemia and insulin resistance index. These results suggest that acute ischemic stroke can activate proinflammatory pathways in the liver by the catecholamines and is associated with the development of hepatic insulin resistance.
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Identification and assessment of potential water quality impact factors for drinking-water reservoirs.
Int J Environ Res Public Health
PUBLISHED: 01-16-2014
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Various reservoirs have been serving as the most important drinking water sources in Zhejiang Province, China, due to the uneven distribution of precipitation and severe river pollution. Unfortunately, rapid urbanization and industrialization have been continuously challenging the water quality of the drinking-water reservoirs. The identification and assessment of potential impacts is indispensable in water resource management and protection. This study investigates the drinking water reservoirs in Zhejiang Province to better understand the potential impact on water quality. Altogether seventy-three typical drinking reservoirs in Zhejiang Province encompassing various water storage levels were selected and evaluated. Using fifty-two reservoirs as training samples, the classification and regression tree (CART) method and sixteen comprehensive variables, including six sub-sets (land use, population, socio-economy, geographical features, inherent characteristics, and climate), were adopted to establish a decision-making model for identifying and assessing their potential impacts on drinking-water quality. The water quality class of the remaining twenty-one reservoirs was then predicted and tested based on the decision-making model, resulting in a water quality class attribution accuracy of 81.0%. Based on the decision rules and quantitative importance of the independent variables, industrial emissions was identified as the most important factor influencing the water quality of reservoirs; land use and human habitation also had a substantial impact on water quality. The results of this study provide insights into the factors impacting the water quality of reservoirs as well as basic information for protecting reservoir water resources.
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The relationship between secondary hyperparathyroidism and thyroid cancer in end stage renal disease: a population based cohort study.
Eur. J. Intern. Med.
PUBLISHED: 01-02-2014
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We conducted a retrospective cohort study to investigate the risk of cancer in end stage renal disease (ESRD) patients with secondary hyperparathyroidism (HPT).
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Correlation between reduction of superior interventricular groove epicardial fat thickness and improvement of insulin resistance after weight loss in obese men.
Diabetol Metab Syndr
PUBLISHED: 01-01-2014
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It has been recognized that reduction of abdominal visceral fat and subcutaneous fat are associated with improvement in insulin-resistance (IR) after weight loss. However, few studies have investigated the correlation of reduction in epicardial adipose tissue (EAT) with improvement of IR index after weight loss in obese non-diabetic men with metabolic syndrome (MetS).
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Iris color and associated pathological ocular complications: a review of epidemiologic studies.
Int J Ophthalmol
PUBLISHED: 01-01-2014
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To elucidate the associations of iris color with major eye diseases.
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Strategies for improving the reporting of human immunophenotypes by flow cytometry.
J Immunother Cancer
PUBLISHED: 01-01-2014
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Flow cytometry is the gold standard for phenotyping and quantifying immune cells. New technologies have greatly increased our capacity to measure both routine and complex immunophenotypes. The reporting of immunophenotype data is not consistent in human studies yet it is quite critical for understanding disease specific changes, responses to immunotherapies, and normal immune homeostasis. Here we examine the barriers that hinder cross comparisons of flow cytometry data collected from human studies and clinical trials.
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Post-meal ?-cell function predicts the efficacy of glycemic control in patients with type 2 diabetes inadequately controlled by metformin monotherapy after addition of glibenclamide or acarbose.
Diabetol Metab Syndr
PUBLISHED: 01-01-2014
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This study aimed to explore parameters which will predict good control of HbA1c after adding a second anti-diabetic drug in patients with type 2 diabetes mellitus (T2DM) inadequately controlled with metformin monotherapy.
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?1,6 GlcNAc branches-modified PTPRT attenuates its activity and promotes cell migration by STAT3 pathway.
PLoS ONE
PUBLISHED: 01-01-2014
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Receptor-like protein tyrosine phosphatases (RPTPs) are type I transmembrane glycoproteins with N-glycans whose catalytic activities are regulated by dimerization. However, the intrinsic mechanism involved in dimerizing processes remains obscure. In this study, receptor protein tyrosine phosphatase rho (PTPRT) is identified as a novel substrate of N-Acetylglucosaminyltransferase V (GnT-V). We show that addition of ?1,6 GlcNAc branches on PTPRT prolongs PTPRT's cell-surface retention time. GnT-V overexpression enhances galectin-3's cell-surface retention and promotes PTPRT's dimerization mediated by galectin-3. Increased dimerization subsequently reduces PTPRT's catalytic activity on the dephosphorylation of signal transducer and activator of transcription 3 (STAT3) at tyrosine residue 705 (pY705 STAT3), then the accumulated pY705 STAT3 translocates into the nucleus. Collectively, these findings provide an insight into the molecular mechanism by which GnT-V promotes cell migration, suggesting that accumulation of ?1,6 GlcNAc branched N-glycans promotes PTPRT's dimerization and decreases its catalytic activity, resulting in enhanced cell migratory capacity.
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Prognostic features of signal transducer and activator of transcription 3 in an ER(+) breast cancer model system.
Cancer Inform
PUBLISHED: 01-01-2014
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The aberrantly expressed signal transducer and activator of transcription 3 (STAT3) predicts poor prognosis, primarily in estrogen receptor positive (ER(+)) breast cancers. Activated STAT3 is overexpressed in luminal A subtype cells. The mechanisms contributing to the prognosis and/or subtype relevant features of STAT3 in ER(+) breast cancers are through multiple interacting regulatory pathways, including STAT3-MYC, STAT3-ER?, and STAT3-MYC-ER? interactions, as well as the direct action of activated STAT3. These data predict malignant events, treatment responses and a novel enhancer of tamoxifen resistance. The inferred crosstalk between ER? and STAT3 in regulating their shared target gene-METAP2 is partially validated in the luminal B breast cancer cell line-MCF7. Taken together, we identify a poor prognosis relevant gene set within the STAT3 network and a robust one in a subset of patients. VEGFA, ABL1, LYN, IGF2R and STAT3 are suggested therapeutic targets for further study based upon the degree of differential expression in our model.
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Behcets disease associated with malignancy: a report of 41 Chinese cases.
Int J Rheum Dis
PUBLISHED: 12-20-2013
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To identify the clinical characteristics of Behcets disease (BD) associated with malignancies.
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Plasma levels of tissue inhibitor of matrix metalloproteinase-1 correlate with diagnosis and prognosis of glioma patients.
Chin. Med. J.
PUBLISHED: 11-19-2013
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There is no validated blood biomarker available for glioma management. Invasive growth is the key feature of glioma. We assessed the clinical usefulness of plasma tissue inhibitor of metalloproteinase 1 (TIMP-1), which has less molecular weight than metalloproteinases, as a potential blood biomarker for glioma.
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Importance of achieving stringent complete response after autologous stem-cell transplantation in multiple myeloma.
J. Clin. Oncol.
PUBLISHED: 11-18-2013
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To study the impact of achieving stringent complete response (sCR), an increasingly attainable goal, after autologous stem-cell transplantation (ASCT) in patients with multiple myeloma (MM).
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Dispersion Force Stabilized Two-Coordinate Transition Metal-Amido Complexes of the -N(SiMe3)Dipp (Dipp = C6H3-2,6-Pr(i)2) Ligand: Structural, Spectroscopic, Magnetic, and Computational Studies.
Inorg Chem
PUBLISHED: 11-18-2013
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A series of high spin, two-coordinate first row transition metal-amido complexes, M{N(SiMe3)Dipp}2 {M = Fe (1), Co (2), or Ni (3); Dipp = C6H3-2,6-Pr(i)2} and a tetranuclear C-H activated chromium amide, [Cr{N(SiMe2CH2)Dipp}2Cr]2(THF) (4), were synthesized by reaction of their respective metal dihalides with 2 equiv of the lithium amide salt. They were characterized by X-ray crystallography, electronic and infrared spectroscopy, SQUID magnetic measurements, and computational methods. Contrary to steric considerations, the structures of 1-3 display planar eclipsed M{NSiC(ipso)}2 arrays and short M-N distances. DFT calculations, corrected for dispersion effects, show that dispersion interactions involving C-H-H-C moieties likely stabilize the structures by 21.1-29.4 kcal mol(-1), depending on the level of the calculations employed. SQUID measurements confirm high spin electron configurations for all the complexes and substantial orbital contributions for 1 and 2.
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Experimental demonstration of elastic optical networks based on enhanced software defined networking (eSDN) for data center application.
Opt Express
PUBLISHED: 11-13-2013
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Due to the high burstiness and high-bandwidth characteristics of the applications, data center interconnection by elastic optical networks have attracted much attention of network operators and service providers. Many data center applications require lower delay and higher availability with the end-to-end guaranteed quality of service. In this paper, we propose and implement a novel elastic optical network based on enhanced software defined networking (eSDN) architecture for data center application, by introducing a transport-aware cross stratum optimization (TA-CSO) strategy. eSDN can enable cross stratum optimization of application and elastic optical network stratum resources and provide the elastic physical layer parameter adjustment, e.g., modulation format and bandwidth. We have designed and verified experimentally software defined path provisioning on our testbed with four real OpenFlow-enabled elastic optical nodes for data center application. The overall feasibility and efficiency of the proposed architecture is also experimentally demonstrated and compared with individual CSO and physical layer adjustment strategies in terms of path setup/release/adjustment latency, blocking probability and resource occupation rate.
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Labeling the nucleocapsid of enveloped baculovirus with quantum dots for single-virus tracking.
Biomaterials
PUBLISHED: 11-05-2013
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Utilization of quantum dots (QDs) for single-virus tracking is highly important for understanding virus infection mechanism. However, QD labeling site of real enveloped viruses has been confined to the external envelope so far, causing the impossibility to monitor the late infection events after the loss of envelope. Herein, a strategy to label the internal nucleocapsid of enveloped virus with QDs was proposed. The nucleocapsid of enveloped baculovirus was self-biotinylated during virus replication process in host cells and subsequently labeled with streptavidin-conjugated QDs (SA-QDs). Such host cell-assisted QD labeling was proved to be reliable, specific, efficient and capable of maintaining virus infectivity. Based on such labeling, critical infection events before and after the envelope loss were monitored in real time, including single virus interacting with late endosomes and the subsequent nucleocapsid transporting into cell nucleus. Thus our established QD labeling of enveloped virus nucleocapsid with QDs enables the comprehensive single-virus tracking for deeply understanding virus infection mechanism.
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Piperine induces apoptosis of lung cancer A549 cells via p53-dependent mitochondrial signaling pathway.
Tumour Biol.
PUBLISHED: 10-27-2013
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The aim of this study was to evaluate the cytotoxic and apoptotic effects of piperine on human lung cancer A549 cells and to explore its mechanisms. Piperine was found to exert the greatest cytotoxic effect against A549 cells in a dose-dependent manner, whereas it showed no effect on WI38 human lung fibroblasts. This cell growth-inhibitory effect might be attributed to cell DNA damage and cytotoxic effects. Besides, piperine had the ability to cause cell cycle arrest in G2/M phase and to activate caspase-3 and caspase-9 cascades in A549 cells. Furthermore, piperine-induced apoptosis could be blocked by the broad caspase inhibitor z-VAD-fmk in majority. In addition, piperine treatment decreased Bcl-2 protein expression, but increased Bax protein expression in A549 cells, which were positively correlated with an elevated expression of p53 compared to control. Taken together, these results suggested that piperine could induce p53-mediated cell cycle arrest and apoptosis via activation of caspase-3 and caspase-9 cascades, as well as increasing the Bax/Bcl-2 ratio. Thus, piperine could be developed as an effective antitumor agent in the prevention and treatment of lung cancer without toxicity to the host.
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Coexistent multiple myeloma or increased bone marrow plasma cells define equally high-risk populations in patients with immunoglobulin light chain amyloidosis.
J. Clin. Oncol.
PUBLISHED: 10-21-2013
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There is consensus that patients with light chain (AL) amyloidosis with hypercalcemia, renal failure, anemia, and lytic bone lesions attributable to clonal expansion of plasma cells (CRAB criteria) also have multiple myeloma (MM). The aim of this study was to examine the spectrum of immunoglobulin AL amyloidosis with and without MM, with a goal of defining the optimal bone marrow plasma cell (BMPC) number to qualify as AL amyloidosis with MM.
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Smoldering multiple myeloma requiring treatment: time for a new definition?
Blood
PUBLISHED: 10-21-2013
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Smoldering multiple myeloma (SMM) bridges the gap between monoclonal gammopathy of undetermined significance (a mostly premalignant disorder) and active multiple myeloma (MM). Until recently, no interventional study in patients with SMM showed improved overall survival (OS) with therapy as compared with observation. A report from the PETHEMA-GEM (Programa Español de Tratamientos en Hematologica) group described both fewer myeloma-related events and better OS among patients with high-risk SMM who were treated with lenalidomide and dexamethasone. This unique study prompted us to review current knowledge about SMM and address the following questions: (1) Are there patients currently defined as SMM who should be treated routinely? (2) Should the definitions of SMM and MM be reconsidered? (3) Has the time come when not treating is more dangerous than treating? (4) Could unintended medical harm result from overzealous intervention? Our conclusion is that those patients with the highest-risk SMM (extreme bone marrow plasmacytosis, extremely abnormal serum immunoglobulin free light chain ratio, and multiple bone lesions detected only by modern imaging) should be reclassified as active MM so that they can receive MM-appropriate therapy and the paradigm of careful observation for patients with SMM can be preserved.
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Association Between Periodontitis Needing Surgical Treatment and Subsequent Diabetes Risk: A Population-Based Cohort Study.
J. Periodontol.
PUBLISHED: 10-21-2013
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Backgrounds: It is well known that diabetic patients have higher extent and severity of periodontitis, but the backward relationship is little investigated. We assessed the relationship between periodontitis needing dental surgery and subsequent type 2 diabetes in those non-diabetes. Methods: This was a retrospective cohort study employing data from the national health insurance system of Taiwan. The periodontitis cohort involved 22,299 patients, excluding those with diabetes already or diagnosed with diabetes within 1 year from baseline. Each study subject was randomly frequency matched by age, gender and index year with 1 individual from the general population without periodontitis. Cox proportional hazards regression analysis was used to estimate the influence of periodontitis on the risk of diabetes. Results: The mean follow up period is 5.47± 3.54 years. Overall, the subsequent incidence of type 2 diabetes was 1.24-fold higher in the periodontitis cohort than in the control cohort, with an adjusted hazard ration of 1.19(95% confidence interval [CI], 1.10-1.29) after controlling for sex, age and co-morbidities. Conclusions: This is the largest and nation-based study examining the risk of diabetes in Asian patients with periodontitis. Those periodontitis patients needing dental surgery have increased risk of future diabetes within 2 years than those periodontitis participants without dental surgery.
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Effect of intragastric balloon on gastric emptying time in humans for weight control.
Clin Nucl Med
PUBLISHED: 10-04-2013
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This study evaluated the effect of fluid-filled intragastric balloon treatment on the scintigraphic gastric emptying times in humans for weight control.
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Transcriptional repressor HipB regulates the multiple promoters in Escherichia coli.
J. Mol. Microbiol. Biotechnol.
PUBLISHED: 09-27-2013
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HipB is a DNA-binding protein in Escherichia coli and negatively regulates its own promoter by binding to the palindromic sequences [TATCCN8GGATA (N represents any nucleotides)] on the hipBA promoter. For such sequences, bioinformatic analysis revealed that there are a total of 39 palindromic sequences (TATCCN(x)GGATA: N is any nucleotides and x is the number of nucleotides from 1 to 30) in the promoter regions of 33 genes on the E. coli genome. Notably, eutH and fadH have two and three TATCCN(x)GGATA palindromic sequences located in their promoters, respectively. Another significant finding was that a palindromic sequence was also identified in the promoter region of hipAB locus, known to be involved in the RelA-dependent persister cell formation in bacteria. Here, we demonstrated that HipB binds to the palindromic structures in the eutH, fadH, as well as the relA promoter regions and represses their expressions. We further demonstrated that HipA enhances the repression of the relA promoter activity by HipB. This effect was not observed with D291A HipA mutant which was previously shown to lack an ability to interact with HipB, indicating that HipA enhances the HipBs repressor activity through direct interaction with HipB.
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Single ZnO microrod ultraviolet photodetector with high photocurrent gain.
ACS Appl Mater Interfaces
PUBLISHED: 09-26-2013
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An Ag/ZnO microrod/Ag ultraviolet photodetector is fabricated, the ZnO microrod shows a hexagonal whispering gallery cavity structure. Upon a 325 nm ultraviolet illumination, the device shows a high sensitivity of 4 × 10(4) A/W and a high photocurrent gain of 1.5 × 10(5) at 5 V bias. Under different illumination power P, the photocurrent Ilight obeys a power law relation Ilight ? P(0.69). The high performance is probably attributed to a Schottky barrier at Ag/ZnO interface and optical whispering gallery mode effect in the ZnO microrod.
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