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Find video protocols related to scientific articles indexed in Pubmed.
Metallofullerenes Encaging Mixed-Metal Clusters: Synthesis and Structural Studies of Gdx Ho3-x N@C80 and Gdx Lu3-x N@C80.
Chemphyschem
PUBLISHED: 09-28-2014
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Metallofullerenes of Gdx Ho3-x N@C80 and Gdx Lu3-x N@C80 encapsulating mixed-metal nitride clusters were synthesized. Spectroscopic characterization of Gdx Ho3-x N@C80 and Gdx Lu3-x N@C80 was employed to reveal their structural and vibrational properties. The structural properties of these species were analyzed by using theoretical calculations. The studies of Gdx Ho3-x N@C80 and Gdx Lu3-x N@C80 laid the foundations for these species to be used as multifunctional molecules.
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Identification of Klebsiella pneumoniae strains harboring inactive extended-spectrum beta-lactamase antibiotic-resistance genes.
Chin. Med. J.
PUBLISHED: 09-06-2014
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The extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae has increasingly become a major contributor to nosocomial infections and can exhibit multiple antibiotic resistance. Previous studies have focused on the resistance genes in ESBL-producing strains, and the resistance-associated genetic environment of non-ESBL-producing strains has been ignored until now. Here, we investigated the occurrence and characteristics of non-ESBL-producing K. pneumoniae, which potentially carries unexpressed resistance genes.
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Lifestyle risks exposure and response predictor of gefitinib in patients with non-small cell lung cancer.
Med. Oncol.
PUBLISHED: 08-08-2014
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Epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) have been shown to improve the prognosis of EGFR-mutated (exon 19/21) non-small cell lung carcinoma (NSCLC). Positive EGFR mutation status is associated with NSCLC in non-smokers. Genetic and environmental factors have been linked to the etiology of EGFR mutations and sensitivity to EGFR-TKIs in non-smoking NSCLC patients. Cooking fume exposure (CFE) has also been proposed as an etiologic factor for NSCLC in non-smokers; however, the association of CFE with EGFR mutation status and EGFR-TKI response is unclear. The objective of this study was to determine the association between CFE and clinical response to EGFR-TKI therapy in NSCLC. The association of CFE, smoking history, occupational hazard exposure, tumor pathological type, EGFR mutation status, environmental exposure, living environment, and performance status with EGFR-TKI efficacy was determined in metastatic NSCLC patients who were treated with EGFR-TKIs (gefitinib or erlotinib). Objective response rate (ORR) and progression-free survival (PFS) were used to evaluate EGFR-TKI response. A total of 273 patients with a median age of 60.97 years (range 27-86 years) were included in this study. The proportion of patients receiving gefitinib and erlotinib was 72.53% (198/273) and 27.47% (75/273), respectively. ORRs (complete+partial responses) to gefitinib and erlotinib treatment were 20.70% (41/198) and 14.67% (11/75), respectively. Of the 273 patients, 98 (36.03%) had CFE and 112 (44.69%) had exposed to tobacco smoke. EGFR mutations were present in 55 patients, including exon 19 deletion (n=43) and exon 21 point mutations (n=12). Of the 55 EGFR mutation-positive patients, 52 (94.5%) had CFE. In the multivariate conditional logistic analysis, clinical response to EGFR-TKI was associated with non-smoking status, EGFR mutation, and CFE. Among these factors, CFE was the strongest predictor of EGFR-TKI response (odds ratio 13.66; 95% confidence interval (CI) 5.66-32.98; P<0.001). PFS was associated with a performance status of 0/1, adenocarcinoma pathological type, non-smoking status, EGFR mutation, and CFE. Among these, CFE was the most important factor for longer PFS (hazard ratio 0.37; 95% CI 0.26-0.52; P<0.001). The median PFS was 15.15 months in patients with CFE and 4.37 months in those without (P<0.0001). Knowledge of CFE history might be useful as a response predictor to EGFR-TKI treatment in NSCLC. Furthermore, CFE history might help to assess EGFR mutation status when genetic testing is not available.
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Surface chemical and local electronic properties of Al(x)Ga(1-x)N epi-layers grown by MOCVD.
Opt Express
PUBLISHED: 08-05-2014
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The surface chemical state and local electronic structure of Al(x)Ga(1-x)N (x = 0~0.45) epi-layers have been systematically investigated by X-ray photoelectron spectroscopy (XPS) and extended X-ray absorption fine structure (EXAFS) spectroscopy. The results show that the surface of Al(x)Ga(1-x)N is a composite of oxide and nitride of gallium and aluminum. In addition, it was identified that the Ga-O components were converted to Al-O components when the Al(x)Ga(1-x)N sample was exposed to air. The EXAFS analysis also reveals that the Ga-N and Ga-Al bond lengths are independent of the Al composition, whereas the Ga-Ga bond length is a function of Al composition.
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Genetic environment of ?-lactamase genes of extended-spectrum ?-lactamase-producing Klebsiella pneumoniae isolates from patients with lower respiratory tract infection in China.
Chin. Med. J.
PUBLISHED: 07-03-2014
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Extended-spectrum ?-lactamase (ESBL)-producing Klebsiella pneumoniae (K. pneumoniae) is one of the most popular pathogens that cause refractory respiratory tract infection. The genetic environment, including insertion sequences and the types of promoter, plays a key role in exploration of the mechanism of prevalence and dismission of the ESBL-producing K. pneumoniae isolates. The aim of the investigation was to target analysis the genetic environment and promoter sequences of blaCTX-M, blaSHV and blaTEM, the most popular ?-lactamase genes harbored by ESBL-producing K. pneumoniae isolates.
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Role of bicyclol in preventing chemotherapeutic agent-induced liver injury in patients over 60 years of age with cancer.
J. Int. Med. Res.
PUBLISHED: 06-05-2014
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To evaluate the efficacy of bicyclol in preventing chemotherapy-induced liver damage.
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Robust efficient estimation of heart rate pulse from video.
Biomed Opt Express
PUBLISHED: 04-01-2014
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We describe a simple but robust algorithm for estimating the heart rate pulse from video sequences containing human skin in real time. Based on a model of light interaction with human skin, we define the change of blood concentration due to arterial pulsation as a pixel quotient in log space, and successfully use the derived signal for computing the pulse heart rate. Various experiments with different cameras, different illumination condition, and different skin locations were conducted to demonstrate the effectiveness and robustness of the proposed algorithm. Examples computed with normal illumination show the algorithm is comparable with pulse oximeter devices both in accuracy and sensitivity.
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Reconfigurable terahertz metamaterial device with pressure memory.
Opt Express
PUBLISHED: 03-26-2014
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We demonstrate a liquid metal-based reconfigurable terahertz (THz) metamaterial device that is not only pressure driven, but also exhibits pressure memory. The discrete THz response is obtained by injecting eutectic gallium indium (EGaIn) into a microfluidic structure that is fabricated in polydimethylsiloxane (PDMS) using conventional soft lithography techniques. The shape of the injected EGaIn is mechanically stabilized by the formation of a thin oxide surface layer that allows the fluid to maintain its configuration within the microchannels despite its high intrinsic surface energy. Although the viscosity of EGaIn is twice that of water, the formation of the surface oxide layer prevents flow into a microchannel unless a critical pressure is exceeded. Using a structure in which the lateral channel dimensions vary, we progressively increase the applied pressure beyond the relevant critical pressure for each section of the device, enabling switching from one geometry to another (split ring resonator to closed ring resonator to an irregular closed ring resonator). As the geometry changes, the transmission spectrum of the device changes dramatically. When the external applied pressure is removed between device geometry changes, the liquid metal morphology remains unchanged, which can be regarded as a form of pressure memory. Once the device is fully filled with liquid metal, it can be erased through the use of mechanical pressure and exposure to acid vapors.
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Multiple cueing dissociates location- and feature-based repetition effects.
Vision Res.
PUBLISHED: 03-03-2014
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There is an extensive literature on the phenomenon of inhibition of return (IOR): When attention is drawn to a peripheral location and then removed, response time is delayed if a target appears in the previously inspected location. Recent research suggests that non-spatial attribute repetition (i.e., if a target shares a feature like color with the earlier, cueing, stimulus) can have a similar inhibitory effect, at least when the target appears in the previously cued location. What remains unknown is whether location- and feature-based inhibitory effects can be dissociated. In the present study, we used a multiple cueing approach to investigate the properties of location- and feature-based repetition effects. In two experiments (detection, and discrimination), location-based IOR was absent but feature-based inhibition was consistently observed. Thus, the present results indicate that feature- and location-based inhibitory effects are dissociable. The results also provide support for the view that the attentional consequences of multiple cues reflect the overall center of gravity of the cues. We suggest that the repetition costs associated with feature and location repetition may be best understood as a consequence of the pattern of activation for object files associated with the stimuli present in the displays.
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Heteroresistance at the single-cell level: adapting to antibiotic stress through a population-based strategy and growth-controlled interphenotypic coordination.
MBio
PUBLISHED: 02-13-2014
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Heteroresistance refers to phenotypic heterogeneity of microbial clonal populations under antibiotic stress, and it has been thought to be an allocation of a subset of "resistant" cells for surviving in higher concentrations of antibiotic. The assumption fits the so-called bet-hedging strategy, where a bacterial population "hedges" its "bet" on different phenotypes to be selected by unpredicted environment stresses. To test this hypothesis, we constructed a heteroresistance model by introducing a blaCTX-M-14 gene (coding for a cephalosporin hydrolase) into a sensitive Escherichia coli strain. We confirmed heteroresistance in this clone and that a subset of the cells expressed more hydrolase and formed more colonies in the presence of ceftriaxone (exhibited stronger "resistance"). However, subsequent single-cell-level investigation by using a microfluidic device showed that a subset of cells with a distinguishable phenotype of slowed growth and intensified hydrolase expression emerged, and they were not positively selected but increased their proportion in the population with ascending antibiotic concentrations. Therefore, heteroresistance--the gradually decreased colony-forming capability in the presence of antibiotic--was a result of a decreased growth rate rather than of selection for resistant cells. Using a mock strain without the resistance gene, we further demonstrated the existence of two nested growth-centric feedback loops that control the expression of the hydrolase and maximize population growth in various antibiotic concentrations. In conclusion, phenotypic heterogeneity is a population-based strategy beneficial for bacterial survival and propagation through task allocation and interphenotypic collaboration, and the growth rate provides a critical control for the expression of stress-related genes and an essential mechanism in responding to environmental stresses.
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Adjuvant Chemotherapy with Docetaxel, Cisplatin, and Continuous-Infusion 5-Fluorouracil for Gastric Cancer: A Phase II Study.
Transl Oncol
PUBLISHED: 01-20-2014
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This study evaluated the efficacy and safety of adjuvant chemotherapy with the docetaxel plus cisplatin and 5-fluorouracil (5-FU) (DCF) regimen in patients with gastric cancer.
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The effects of manure and nitrogen fertilizer applications on soil organic carbon and nitrogen in a high-input cropping system.
PLoS ONE
PUBLISHED: 01-01-2014
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With the goal of improving N fertilizer management to maximize soil organic carbon (SOC) storage and minimize N losses in high-intensity cropping system, a 6-years greenhouse vegetable experiment was conducted from 2004 to 2010 in Shouguang, northern China. Treatment tested the effects of organic manure and N fertilizer on SOC, total N (TN) pool and annual apparent N losses. The results demonstrated that SOC and TN concentrations in the 0-10cm soil layer decreased significantly without organic manure and mineral N applications, primarily because of the decomposition of stable C. Increasing C inputs through wheat straw and chicken manure incorporation couldn't increase SOC pools over the 4 year duration of the experiment. In contrast to the organic manure treatment, the SOC and TN pools were not increased with the combination of organic manure and N fertilizer. However, the soil labile carbon fractions increased significantly when both chicken manure and N fertilizer were applied together. Additionally, lower optimized N fertilizer inputs did not decrease SOC and TN accumulation compared with conventional N applications. Despite the annual apparent N losses for the optimized N treatment were significantly lower than that for the conventional N treatment, the unchanged SOC over the past 6 years might limit N storage in the soil and more surplus N were lost to the environment. Consequently, optimized N fertilizer inputs according to root-zone N management did not influence the accumulation of SOC and TN in soil; but beneficial in reducing apparent N losses. N fertilizer management in a greenhouse cropping system should not only identify how to reduce N fertilizer input but should also be more attentive to improving soil fertility with better management of organic manure.
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Job Burnout, Mood State, and Cardiovascular Variable Changes of Doctors and Nurses in a Children's Hospital in China.
ISRN Nurs
PUBLISHED: 01-01-2014
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Aims. This study examines mood and cardiovascular variables related to job stress and burnout in hospital personnel. Main Methods. 400 nurses and physicians from a children's hospital in China were recruited. Participants completed job stress, burnout, and mood state questionnaires. Cardiovascular variables such as body mass index (BMI), triglyceride (TG), and high density lipoprotein (HDL) were measured. Key Findings. Job stress and burnout were significantly associated with mood state. Statistically significant correlations were found between triglyceride levels and job stress scores (r = 0.175, P < 0.01), BMI and job stress scores (r = 0.121, P < 0.05), and HDL levels and job stress scores (r = -0.117, P < 0.05). Significance. Mood state changes may be related to job stress and job burnout, in turn, associated with triglycerides and HDL levels. Public health implications and interventions are discussed.
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Beyond the inhibition of return of attention: reduced habituation to threatening faces in schizophrenia.
Front Psychiatry
PUBLISHED: 01-01-2014
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Attention deficits are prominent among the core symptoms of schizophrenia. A recent meta-analysis has suggested that patients with schizophrenia have a deficit in endogenous disengagement of attention. In this research, we used a standard spatial cueing paradigm to examine whether the attention deficit of such patients is due to impaired attentional disengagement or defective novelty detection/habituation processes. In a spatial cueing procedure with peripheral non-predictive cues and a detection task, we manipulated the valence of either the cue or the target (i.e., a threatening vs. scrambled face) in two separate experiments. The control group exhibited a smaller inhibition of return (IOR) effect only when the target had an emotional load, not when the cue had an emotional load. In the patient group, a larger emotional effect appeared when the threatening face was the target; by contrast, no effect of valence was observed when the threatening face was the cue: IOR was delayed or completely absent independently of valence. The present findings are in conflict with the hypothesis that IOR is due to the disengagement of attention and the subsequent inhibition to return. Instead, they seem to suggest a cost in detecting new information at a previously cued location. From this perspective, it seems that patients with schizophrenia might have a deficit in detecting new information and considering it as new in the current context.
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[Preparation and application of solid phase extraction packing of zirconia microsphere coated with sulfonated crosslinked polystyrene].
Se Pu
PUBLISHED: 12-28-2013
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Zirconia microsphere was prepared by polymerization-induced colloid aggregation (PICA) method and carbon-carbon double bond was grafted onto its surface by titanic acid ester coupling reagent. Poly(styrene-divinylbenzene) was synthesized by free radical polymerization by using styrene, divinylbenzene and carbon-carbon double bond on the microsphere surface in solution system, so the polymer was coated on the microsphere surface. After the benzene ring of the polymer was sulfonated, the cation exchange packing for solid phase extraction (SPE) was obtained. The material was characterized by Fourier transform infrared spectroscopy, scanning electron microscope and X-ray energy dispersive spectroscopy. Three herbicides of mesotrione, atrazine and acetochlor in water were determined by the SPE cartridge coupled with high performance liquid chromatography (HPLC). In the range of 0.5 - 3.0 mg/L, the relationships between the peak areas and mass concentrations of mesotrione, atrazine and acetochlor were linear with the correlation coefficients of 0.9936, 0.9925, 0.9919, respectively. The limits of detection were 5.41, 6.72 and 13.4 microg/L for mesotrione, atrazine and acetochlor, respectively. The results showed that the zirconium dioxide microspheres coated with polymer have diameters in the range of about 6 to 8 microm, the SPE cartridges of which have high adsorption rate for the targets.
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Phase noise tolerant inter-carrier-interference cancellation for WDM superchannels with sub-Nyquist channel spacing.
Opt Express
PUBLISHED: 10-10-2013
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We propose and demonstrate a novel multi-input multi-output (MIMO) equalization based inter-carrier-interference (ICI) cancellation approach employing constant modulus algorithm (CMA) for supperchanels with sub-Nyquist channel spacing, where optical combs are used as optical sources. Compared with the least mean square (LMS) algorithm based ICI canceller, the proposed approach has comparable capability to accomplish the ICI mitigation for 56 Gbaud dual-polarization quadrature phase shift keying (DP-QPSK) signals with tight channel spacing till 50 GHz. In particular, compared with the LMS-MIMO based ICI canceller, the optical linewidth tolerance of 6 MHz is relaxed to 20 MHz given a 1dB required optical signal-to-noise ratio (OSNR) penalty for the CMA-MIMO based ICI canceller. Meanwhile, the CMA-MIMO based ICI canceller is ideal for real-time processing, since the number of parallel processing pipelines can be greater than 240 even in the presence of large linewidth.
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Surfactant-free hydrothermal synthesis of sub-10 nm ?-Fe2O3-polymer porous composites with high catalytic activity for reduction of nitroarenes.
Chem. Commun. (Camb.)
PUBLISHED: 09-18-2013
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Porous ?-Fe2O3-polymer composites were synthesized by a novel one-pot surfactant-free hydrothermal approach. The ?-Fe2O3-polymer composites consisting of 3.5 nm ?-Fe2O3 nanoparticles and porous polymers exhibited high catalytic activity and recycling performance in the reduction of nitroarenes.
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Effects of display complexity on location and feature inhibition.
Atten Percept Psychophys
PUBLISHED: 08-03-2013
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Inhibition of return refers to the lengthening of reaction times (RTs) to a target when a preceding stimulus has occupied the same location in space. Recently, we observed a robust inhibitory effect for color and shape in moderately complex displays: It is more difficult to detect a target with a particular nonspatial attribute if a stimulus with the same attribute was recently the focus of attention. Such nonspatial inhibitory effects have not generally been found in simpler displays. In the present study, we test how location-based and nonspatial inhibitory effects vary as a function of display complexity (eight, six, four, and two locations). The results demonstrated that (1) location-based inhibition effects were much stronger in more complex displays, whereas the nonspatial inhibition was only slightly stronger in more complex displays; (2) nonspatial inhibitory effects emerged at longer stimulus onset asynchronies than did location-based effects; and (3) nonspatial inhibition appeared only when cues and targets occurred in the same locations, confirming that pure feature repetition does not produce a cost. Taken together, the results are consistent with perceptual processes based on object files that are organized by spatial location. Using somewhat more complex displays than are most commonly employed provides a more sensitive method for observing the role of inhibitory processes in facilitating visual search. In addition, using a relatively wide set of cue-target timing relationships is necessary in order to clearly see how inhibitory effects operate.
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Cyclooxygenase-2 promotes hepatocellular apoptosis by interacting with TNF-? and IL-6 in the pathogenesis of nonalcoholic steatohepatitis in rats.
Dig. Dis. Sci.
PUBLISHED: 07-23-2013
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The underlying mechanisms of nonalcoholic steatohepatitis (NASH) are poorly understood, and little is known about hepatocellular apoptosis in NASH. Cyclooxygenase (COX)-2, the key enzyme in eicosanoid metabolism, is highly expressed in NASH. COX-2 can also regulate the release of mediators of inflammation, such as tumor necrosis factor (TNF)-? and interleukin (IL)-6. The aim of our study was to evaluate the effects of COX-2 on hepatocellular apoptosis and the mechanism of the action in the pathogenesis of NASH in rats.
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Abnormal activity of default mode network in GERD patients.
BMC Neurosci
PUBLISHED: 07-01-2013
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Abnormal processing of esophageal sensation at the level of the central nervous system has been proven to be involved in gastroesophageal reflux disease (GERD). However, most studies were focused on the possible functions of perceptual processing related network during task status, little attention has been paid to default mode network, which has been manifested to be important in the pathogenesis of many diseases. In our study, we compared the brain activity characteristic in GERD patients with the healthy subjects (HS) at baseline, looking for whether activities of default mode network were abnormal in GERD patients and attempting to identify their possible roles in GERD. In present study, fractional amplitude of low-frequency fluctuation was adopted to detect the brain activities at baseline. Group-level analyses were conducted by one-sample t test within groups (voxel thresholds were p<0.001 and cluster level>42, corrected P<0.05) and independent-samples t test between groups (p<0.01 and cluster level>90, corrected P<0.05) using SPM5.
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Concentration of broadband terahertz radiation using a periodic array of conically tapered apertures.
Opt Express
PUBLISHED: 06-06-2013
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We describe the optical concentration properties of periodic arrays of conically tapered metallic apertures measured using terahertz (THz) time-domain spectroscopy. As a first step in this process, we optimize the geometrical properties of individual apertures, keeping the output aperture diameter fixed, and find that the optimal taper angle is 30°. A consequence of increasing the taper angle is that the effective cutoff frequency red shifts, which can be readily explained using conventional waveguide theory. We then fabricate and measure the transmission properties of a periodic (hexagonal) array of optimized tapered apertures. In contrast to periodic arrays of subwavelength apertures in thin metal films, which are characterized by narrowband transmission resonances associated with the periodic spacing, here we observe broadband enhanced transmission above the effective cutoff frequency. Further enhancement in the concentration capabilities of the array can be achieved by tilting the apertures towards the array center, although the optical throughput of individual tapered apertures is reduced with increasing tilt angle. Finally, we discuss possible future directions that utilize cascaded structures, as a means for obtaining further enhancement in the amplitude of the transmitted THz radiation.
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The neurobehavioral impact of manganese: results and challenges obtained by a meta-analysis of individual participant data.
Neurotoxicology
PUBLISHED: 02-06-2013
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Results from a meta-analysis of aggregated data provoked a new analysis using individual data on the neuropsychological performance of occupationally exposed workers. Data from eight studies examining 579 exposed and 433 reference participants were included, 28 performance variables analyzed. The performance scores were adjusted for well-known individual-level covariates; the influence of possible, but unknown study-level covariates was attenuated by means of a z-normalization. Associations between performance and exposure were estimated by ANOVAs and ANCOVAs, the latter representing multi-level models. Four cognitive and motor performance variables each indicated significantly lower performances of exposed individuals when confounding was considered; slowed motor performances and deficits in attention and short-term memory were found. Performance on a single test was significantly related to the biomarker manganese in blood. The outcomes on susceptibility were weak. The slowing of responses was the most distinct feature of performances of exposed workers. It remains unclear, whether this result is related to the employed tests or provides important information about early stages of the neurotoxic impairment. More specific cognitive tests need to be employed to answer this question. The lack of dose-response relationships was related to features of the biomarker: it does not reflect the Mn in brain responsible for changes in performances.
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The Diagnostic Significance of Coapplying a Rabeprazole Test with the SF-36 for Gastroesophageal Reflux Disease.
Gastroenterol Res Pract
PUBLISHED: 01-07-2013
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Gastroesophageal reflux disease is a diversity disease that affects life quality of people in the world. Due to the complicated pathogenesis and variations in clinical manifestations, there is still no true gold standard for GERD diagnosis, and it is still difficult to diagnose this disease in some patients. The proton pump inhibitors diagnostic test (the PPI test) is noninvasive, of low cost, tied to treatment, and widely accepted. Our aim is to evaluate the diagnostic significance of coapplying a rabeprazole test with the SF-36 for GERD in this study. Our study shows that the SF-36 in combination with the rabeprazole test can screen GERD patients and increase the sensitivity and specificity of GERD diagnosis through reference to the change in SF-36 score before and after the treatment (65 in the trial).
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CCR7 expression and intratumoral FOXP3+ regulatory T cells are correlated with overall survival and lymph node metastasis in gastric cancer.
PLoS ONE
PUBLISHED: 01-01-2013
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The aim of this study was to investigate the prognostic value of chemokine receptor CCR7 expression and intratumoral FOXP3(+) regulatory T cells (Tregs) in gastric cancer. CCR7(+) tumor cells and FOXP3(+) Tregs were assessed by immunohistochemistry in tissue microarrays containing gastric cancer from 133 patients. Prognostic effects of low or high CCR7 and FOXP3 expression were evaluated by Cox regression and Kaplan-Meier analysis, as well as the correlation between CCR7 positive score and intratumoral FOXP3(+) cell number in a longitudinal assessment. The analysis showed that the high expression levels of CCR7 and FOXP3 were detected in 69.9% and 65.4% of cases, respectively. High CCR7 expression in gastric cancer cells was significantly associated with poor overall survival (OS) (P = 0.010) and lymph node metastasis (P = 0.009), and was an independent factor for worse OS (P = 0.023) by multivariate analysis. High numbers of intratumoral FOXP3(+) Tregs significantly correlated with shorter OS (P = 0.021) and lymph node metastasis (P = 0.024), and was also an independent factor for adverse OS (P = 0.035). Furthermore, there was a significantly positive correlation between CCR7 positive score and intratumoral FOXP3(+) cell number (r = 0.949, P<0.001). These results revealed that CCR7 expression in gastric cancer cells and intratumoral FOXP3(+) Tregs could be considered as a co-indicator of clinical prognosis of gastric cancer.
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Engineering the properties of terahertz filters using multilayer aperture arrays.
Opt Express
PUBLISHED: 09-22-2011
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We experimentally demonstrate the ability to create additional transmission resonances in a double-layer aperture array by varying the interlayer gap spacing. In the case of periodic aperture arrays, these additional resonances are sharply peaked, while for random aperture arrays the resonances are broad. Surprisingly, these additional resonances only occur when the interlayer gap spacing is greater than half the aperture spacing on a single array. Since there is no corresponding periodicity in the random arrays, these resonances occur regardless of how small the gap spacing is made. This phenomenon can be accurately modeled only if the correct frequency-dependent complex dielectric function of a metal film perforated with subwavelength apertures is used. Using THz time-domain spectroscopy, we are able to directly obtain the complex dielectric response function from the THz experimental transmission measurements. We conclude by demonstrating several passive free-space THz filters using multilayer aperture arrays. Importantly, we show that the magnitude of the lowest order resonance can be approximately maintained, while the background transmission can be significantly suppressed leading to a significant improvement in the optical filter fidelity.
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Amplification of the telomerase RNA component gene in the process of human esophageal carcinogenesis.
Tohoku J. Exp. Med.
PUBLISHED: 05-21-2011
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Amplification of the human telomerase RNA component (hTERC) gene occurs early in cervical cancer development. Telomerase, the product of the hTERC gene, plays an important role in tumor cell apoptosis and genomic stability. Given the numerous similarities between esophageal and cervical cancers, we hypothesized that hTERC gene amplification may also be related with esophageal cancer development. We therefore examined 189 tissue sections from 63 cases of esophageal cancer and preneoplastic lesions. hTERC gene amplification in the lesions was detected by interphase fluorescence in situ hybridization. Of the 189 tissue sections, 149 were successfully evaluated (40 samples were excluded because of inappropriately preparation) and were classified as normal (n=45), atypical hyperplasia I (n=27), atypical hyperplasia II/III (n=22), and squamous cell carcinomas (SCCs; the most common type of esophageal cancer) (n=55). hTERC gene expression was not detected in normal esophageal tissue, whereas its expression was detected in atypical hyperplasias I (25.9%), atypical hyperplasia II/III (54.5%), and SCCs (90.9%) (p<0.05). The average copy numbers of hTERC in atypical hyperplasias I and II/III, as well as SCCs were 2.19, 2.35, and 2.64, respectively. In particular, the numbers of abnormal nuclei in atypical hyperplasias II/III were significantly higher than those of in atypical hyperplasia I (p<0.05). The hTERC gene amplification was not related with patient gender, histological stage, lymph nodes metastasis, and SCC differentiation grade (p>0.05). All these findings suggest that hTERC gene amplification is associated with SCC development.
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Statistical means to enhance the comparability of data within a pooled analysis of individual data in neurobehavioral toxicology.
Toxicol. Lett.
PUBLISHED: 04-28-2011
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Meta-analyses of individual participant data (IPD) provide important contributions to toxicological risk assessments. However, comparability of individual data cannot be taken for granted when information from different studies has to be summarized. By means of statistical standardization approaches the comparability of data might be increased. An analysis of individual data on the neurobehavioral impact of manganese (Mn) exemplifies challenges and effects of a multilevel statistical procedure. Confounding from individual-level and study-level covariates was shown by analyses of variance, but could be reduced by linear regressions and z-normalization using data of the respective control groups. Fixed models that were used to estimate the impact of the neurotoxic exposure, provided evidence that the employed procedures, especially the z-normalization, effectively reduced variance that was unrelated to the neurotoxic exposure. Even after this statistical treatment the fixed effect models revealed differences among studies that did not seem to be exhaustively explicable by concentration differences obvious from the Mn biomarker at hand. IPD studies using confounded endpoints as effects markers can be reasonably summarized when appropriate statistical operations are employed. For the data at hand the proposed normalization allowed new insights into exposure-effect relationships, in general it appears appropriate to investigate the effect of the independent variable more closely.
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Emotional and neurobehavioural status in chronic pain patients.
Pain Res Manag
PUBLISHED: 03-04-2011
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To investigate the emotional and neurobehavioural status of patients suffering from chronic pain.
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Carbon nanotubes enhance cytotoxicity mediated by human lymphocytes in vitro.
PLoS ONE
PUBLISHED: 02-28-2011
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With the expansion of the potential applications of carbon nanotubes (CNT) in biomedical fields, the toxicity and biocompatibility of CNT have become issues of growing concern. Since the immune system often mediates tissue damage during pathogenesis, it is important to explore whether CNT can trigger cytotoxicity through affecting the immune functions. In the current study, we evaluated the influence of CNT on the cytotoxicity mediated by human lymphocytes in vitro. The results showed that while CNT at low concentrations (0.001 to 0.1 µg/ml) did not cause obvious cell death or apoptosis directly, it enhanced lymphocyte-mediated cytotoxicity against multiple human cell lines. In addition, CNT increased the secretion of IFN-? and TNF-? by the lymphocytes. CNT also upregulated the NF-?B expression in lymphocytes, and the blockage of the NF-?B pathway reduced the lymphocyte-mediated cytotoxicity triggered by CNT. These results suggest that CNT at lower concentrations may prospectively initiate an indirect cytotoxicity through affecting the function of lymphocytes.
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Cough reflex sensitivity and airway inflammation in patients with chronic cough due to non-acid gastro-oesophageal reflux.
Respirology
PUBLISHED: 02-24-2011
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The aim of this study was to explore the pathogenesis of chronic cough caused by non-acid reflux.
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A phase II study of neoadjuvant chemoradiotherapy with oxaliplatin and capecitabine for rectal cancer.
Cancer Lett.
PUBLISHED: 02-21-2011
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This study evaluated the efficacy and safety of neoadjuvant chemoradiotherapy with the XELOX regimen in rectal cancer patients.
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Brain-derived neurotrophic factor signalling mediates antidepressant effects of lamotrigine.
Int. J. Neuropsychopharmacol.
PUBLISHED: 09-16-2010
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The anticonvulsant drug lamotrigine has been shown to produce antidepressant effects in patients with bipolar disorder. To date, only a few preclinical studies have been conducted using lamotrigine treatment in the forced swim test (FST), an animal model of depression with low face validity. The underlying mechanisms by which lamotrigine works have not been well characterized either. This study extends earlier work on the role of brain-derived neurotrophic factor (BDNF) in regulating the antidepressant actions of lamotrigine. We showed that in rats subjected to chronic unpredictable stress, chronic administration of 30 mg/kg lamotrigine ameliorates behavioural deficits of stressed rats in both sucrose preference test (SPT) and novelty-suppressed feeding test (NSFT). In parallel, chronic lamotrigine treatment up-regulates frontal and hippocampal BDNF protein expression in both naive and stressed animals, and restores the stress-induced down-regulation of BDNF levels. In addition, inhibition of BDNF signalling by infusion of K252a, an inhibitor of the BDNF receptor TrkB, blocks the antidepressant effects of lamotrigine in SPT, NSFT and FST. Taken together, this study provides further evidence that BDNF is an essential mediator for the antidepressant effects of lamotrigine.
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[Changes of exercise and the clinical effects among eldly non-small cell lung cancer survivors].
Zhongguo Fei Ai Za Zhi
PUBLISHED: 08-03-2010
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Exercise can improve circulation, muscular strength and happiness of cancer survivors. But more data were needed to demonstrate both the exercise ability of cancer suivivors after pulmonary lobectomy and the influences of exercise on their survivals. The aim of this study was to examine changes of exercise and its clinical effects among eldly non-small cell lung cancer survivors.
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Brain processing of visceral sensation upon esophageal chemical stimulation in different types of GERD.
Eur J Radiol
PUBLISHED: 03-26-2010
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We designed to investigate the cortical response to esophageal acid exposure in different types of gastroesophageal reflux disease (GERD) by functional magnetic resonance imaging (fMRI). Fifteen healthy volunteers, 13 with reflux esophagitis (RE), 12 with non-erosive reflux disease with abnormal acid reflux (NERD+) and nine with non-erosive reflux disease with normal acid reflux (NERD-) received intraesophageal perfusion with isotonic saline followed by 0.1 N hydrochloric acid. Modified block-design model of fMRI scanning was performed simultaneously to the intraesophageal perfusion. The sensitized regions in different types of GERD were not completely identical but were more widely distributed compared to the sensitized regions in the healthy individuals. The activated intensity of the ACC was significantly higher in the healthy volunteers compared to the GERD patients (P<0.001). Nevertheless, healthy volunteers exhibited a significantly lighter intensity in the right side of the DLPFC (P<0.001) and a lower intensity in the left side of the insula than the GERD patients (P<0.05). In conclusion, the underlying central mechanisms of esophageal visceral sensation in different types of GERD patients are quite different. The deactivation of the ACC, the activation of the right side of the DLPFC and the right side of the insula may play an important role in the occurrence of GERD.
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The mood stabilizer lamotrigine produces antidepressant behavioral effects in rats: role of brain-derived neurotrophic factor.
J. Psychopharmacol. (Oxford)
PUBLISHED: 02-01-2010
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The anticonvulsant drug lamotrigine has been shown to produce strong antidepressant effects in the treatment of patients with bipolar disorder. However, to date there are few preclinical reports on its behavioral actions in animal models of depression or its underlying molecular mechanisms. The current study investigated the effects of lamotrigine in the forced swimming test and the learned helplessness test. The results demonstrate that both 15 and 30 mg/kg acute treatment of lamotrigine significantly reduced immobility in the forced swimming test without affecting locomotor activity. Sub-chronic twice daily injections of 30 mg/kg lamotrigine robustly decreased escape failures in animals that had developed learned helplessness symptoms. In parallel, the sub-chronic lamotrigine treatment also up-regulated frontal and hippocampal brain-derived neurotrophic factor expression in both naive and stressed animals and restored the stress-induced down-regulation of brain-derived neurotrophic factor expression. This study provides further evidence for the use of lamotrigine as a novel antidepressant in the treatment of bipolar disorders.
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Simple construction of chimeric hairpin RNA for virus resistance in plants.
J. Virol. Methods
PUBLISHED: 01-08-2010
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RNA silencing has been adopted to develop virus-resistant plants through expression of virus-derived hairpin RNAs. Due to the high sequence specificity of RNA silencing, this technology has been limited to the targeting of single viruses. Simultaneous targeting of multiple viruses or plant genes can be achieved by using a chimeric cassette. In this study, a simple method was developed to construct chimeric hairpin RNA rapidly and efficiently. This method splices two DNA fragments from viruses or plant genes to be a chimeric sequence using Overlap Extension PCR (OE-PCR); then this chimeric sequence was assembled with an intron sequence to generate an intron-containing hairpin RNA construct in one step mediated by OE-PCR. This method is neither dependent on restriction enzymes nor requires expensive consumables, so a chimeric hairpin RNA can be constructed rapidly and costlessly. Two chimeric hairpin RNA constructs were amplified successfully using this method, with the targeting sequences from both papaya ringspot virus (PRSV) and two plant genes encoding translation initiation factors eIF4E and eIFiso4E. This novel method is a useful strategy to construct chimeric hairpin RNA for RNA silencing in plants.
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PI3K/AKT mediated p53 down-regulation participates in CpG DNA inhibition of spontaneous B cell apoptosis.
Cell. Mol. Immunol.
PUBLISHED: 07-02-2009
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The unmethylated CpG DNA can prevent spontaneous apoptosis of B cells. However, the precise mechanisms by which CpG DNA blocks apoptosis remain unclear. In this study, we showed B cell apoptosis was significantly inhibited by addition of CpG DNA. Treatment of CpG DNA could reduce the expression of caspase 3, increase IAP and Bcl-xL expressions, and inhibit p53 protein expression which level was increased in B cell spontaneous apoptosis at 24 h. AKT kinase activity was increased with the incubation of CpG DNA. The wortmannin and Ly294002 could abrogate the protection of B cell from apoptosis by CpG DNA. The up-regulations of Bcl-xL and IAP by CpG DNA were not inhibited when blocking PI3K by specific inhibitor Ly294002, while the inhibition of p53 by CpG DNA could be blocked by Ly294002. These results demonstrated that the inhibition of spontaneous B cell apoptosis by CpG DNA was correlated to up-regulation of Bcl-xL, IAP and down-regulation of p53 and caspase 3. CpG DNA inhibition of p53 is mediated through PI3K/AKT signaling.
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Isolation rearing induces social and emotional function abnormalities and alters glutamate and neurodevelopment-related gene expression in rats.
Prog. Neuropsychopharmacol. Biol. Psychiatry
PUBLISHED: 05-06-2009
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Isolation rearing induces various cognitive abnormalities such as reversal learning deficits and reduced prepulse inhibition in rats. However, there are few reports in the literature on its effects on social and emotional functions. In the current study we aimed to address these issues and demonstrated that isolation rearing induced aggression and impaired social recognition, produced moderate anxiogenic effects in the elevated-plus maze, and resulted in hyperactivity in a novel open field. We also found NR2A, NR2B, PSD-95 and SAP-102 mRNA expression were significantly up-regulated in the hippocampus while NR2B was down-regulated in prefrontal cortex in response to isolation rearing. This study advances the use of social isolation as an animal model for studying etiological mechanisms of various neuropsychiatric disorders.
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Aberrant DNA methylation profile of hepatocellular carcinoma and surgically resected margin.
Cancer Sci.
PUBLISHED: 03-25-2009
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Field cancerization currently described the theory of tumorigenesis and, until now, has been described in almost all organ systems except in liver. For this reason, we explore the presence of field cancerization in liver and its underlying clinical implication in hepatocellular carcinoma (HCC). In our study, methylation profile of HCC and surgically resected margin (SRM) were established by methylation-specific PCR. Liver cirrhosis (LC), chronic hepatitis and normal liver were treated in the same way as the background control. The correlation analysis among the methylation profile of HCC, SRM and clinicopathological data of HCC patients was made respectively. Our results showed that methylation abnormities related to HCC, but not background disease existed in histologically negative SRM. Monoclonal and polyclonal models may coexist in field cancerization in liver. Patients with RIZ1 methylation in SRM had a shorter disease free survival. The local recurrence trend of early and later recurrence in HCC is potentially related to a second field tumor. From these results, we can suggest that field cancerization exists in liver. The study of field cancerization in liver plays an important role in hepatocarcinogenesis. Second field tumor derived form field cancerization may have important implications in HCC prognosis assessment that is worthy of further study.
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[Determination of dichloromethane and trichloromethane residues in ranitidine hydrochloride by headspace liquid phase microextraction coupled with gas chromatography].
Se Pu
PUBLISHED: 03-02-2009
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A method for the determination of residual dichloromethane and trichloromethane in ranitidine hydrochloride by headspace liquid phase microextraction coupled with gas chromatography (GC) was developed. A homemade device was used to protect the organic drop. The effects of the nature of extraction solvent, extraction time, extraction temperature and microdrop volume on the extraction efficiency were investigated separately. The optimal experimental conditions were as follows: 2 microL of n-tridecane as extraction solvent, 30 min of extraction time, 60 degrees C of extraction temperature. The correlation coefficients of linear calibration curve were 0.9733 and 0.9724 within the concentration ranges of dichloromethane (1-10 microg/g) and trichloromethane (1-10 microg/g), respectively. The detection limits of dichlormethane and trichloromethane were 0.0273 microg/g and 0.0410 microg/g, respectively, the relative standard deviations were lower than 4.36% and 5.89%, and the recoveries of the method were 93.6%-102% and 98.1% respectively. The method is simple and reliable.
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[Effect of different doses of perindopril on myocardial energy expenditure in patients with heart failure following myocardial infarction].
Nan Fang Yi Ke Da Xue Xue Bao
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To investigate the changes of myocardial energy expenditure in patients with heart failure following myocardial infarction after treatment with different doses of perindopril.
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Thioredoxin, a novel oxidative stress marker and cognitive performance in chronic and medicated schizophrenia versus healthy controls.
Schizophr. Res.
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Oxidative stress-induced damage to neurons may contribute to cognitive deficits during aging and in neurodegenerative disorders. Schizophrenia has a range of cognitive deficits that may evolve from oxidative stress. Thioredoxin (TRX), a redox-regulating protein with antioxidant activity recognized as an oxidative-stress marker has recently been found to be involved in pathogenesis and psychopathology of schizophrenia. The aim of this study was to examine the association of TRX with cognitive deficits in schizophrenia. We recruited 45 chronic schizophrenic patients and 66 healthy control subjects and examined the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and serum TRX in both groups. Schizophrenic symptoms were assessed using the positive and negative syndrome scale (PANSS). We found no significant difference in TRX levels between patients and healthy controls. Cognitive scores on the RBANS and four of its five subscales (all p<0.001) except for the Visuospatial/Constructional index (p>0.05) were significantly lower in schizophrenic patients than normal controls. For the patients, TRX was inversely associated with the Attention domain of cognitive deficits in schizophrenia; however, TRX was positively associated with Attention in controls. The significantly lower TRX levels in attention impaired schizophrenia compared to controls suggest that oxidative stress may be involved in the cognitive impairment, especially attention in schizophrenia. The differential association of TRX and cognitive performance in schizophrenia and controls may be related to the impaired oxidative stress status of schizophrenia patients.
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Reconfigurable plasmonic devices using liquid metals.
Opt Express
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We experimentally demonstrate an approach to create reconfigurable plasmonic devices in which the geometry of the device can be changed dramatically. The specific embodiment we present utilizes eutectic gallium indium (EGaIn), a metal that is liquid at room temperature, which is injected into or withdrawn from channels encapsulated by a polydimethylsiloxane (PDMS) bullseye mold fabricated on a gold coated substrate. Using terahertz (THz) time-domain spectroscopy, we measure the enhanced transmission properties of a single subwavelength aperture surrounded by differing numbers of concentric annular EGaIn rings. The results obtained from different device geometries, with either a single or multiple rings, are performed using a single device, demonstrating true reconfigurability. We explain the properties of the observed temporal waveforms using a simple time-domain model. This represents, we believe, a first step in developing more complex reconfigurable plasmonic devices.
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Predominant characteristics of CTX-M-producing Klebsiella pneumoniae isolates from patients with lower respiratory tract infection in multiple medical centers in China.
FEMS Microbiol. Lett.
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From February 2010 to July 2011, 183 of 416 presumptive Klebsiella pneumoniae isolates with reduced susceptibility to third-generation cephalosporins from patients with lower respiratory tract infection were collected from seven tertiary hospitals in China. Phenotypic and genotypic methods were employed to characterize 158 extended-spectrum ?-lactamase (ESBL)-producers. Among the 158 isolates analyzed, 134 (84.8%) harbored bla(CTX-M) , within which the most predominant ESBL gene was CTX-M-14 (49.4%), followed by CTX-M-15 (12.0%) and CTX-M-27 (10.8%). Also, 120 (75.9%) harbored bla(SHV) . One novel SHV variant, bla(SHV -142) with T18A and L35Q substitutions, was identified. Ninety-one isolates carried bla(TEM-1). An isolate containing bla(TEM-135) was first identified in Klebsiella spp. bla(KPC)-2) was detected in 5 isolates. More than one ESBL combination was detected in 18 isolates (11.4%). Fifty-four (34.2%) isolates demonstrated the multidrug resistant (MDR) phenotype. Seventy-four sequence types (STs) were identified, which showed large genetic background diversity in ESBL-producing K. pneumoniae isolates from the six areas. This is the first report on the high prevalence of CTX-M-27 in China with the possible transmission of a single clone (ST48). The correlated surveillance of organisms with MDR phenotype should be investigated in future.
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Liquid metal-based plasmonics.
Opt Express
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We demonstrate that liquid metals support surface plasmon-polaritons (SPPs) at terahertz (THz) frequencies, and can thus serve as an attractive material system for a wide variety of plasmonic and metamaterial applications. We use eutectic gallium indium (EGaIn) as the liquid metal injected into a polydimethylsiloxane (PDMS) mold fabricated by soft lithography techniques. Using this approach, we observe enhanced THz transmission through a periodic array of subwavelength apertures. Despite of the fact that the DC conductivity of EGaIn is an order of magnitude smaller than many conventional metals, we clearly observe well-defined transmission resonances. This represents a first step in developing reconfigurable and tunable plasmonic devices that build upon well-developed microfluidic capabilities.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.