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Find video protocols related to scientific articles indexed in Pubmed.
Prognostic significance of circulating CD19+ B lymphocytes in EBV-associated nasopharyngeal carcinoma.
Med. Oncol.
PUBLISHED: 09-03-2014
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In this retrospective study, the correlation between pre- and post-treatment plasma Epstein-Barr virus (EBV) DNA and circulating immune subsets as well as the prognostic implications was investigated in nasopharyngeal carcinoma (NPC) patients. Patients (n=356) were diagnosed and received comprehensive treatment at the First People's Hospital of Foshan from 2006 to 2010. Pre- and post-treatment plasma EBV DNA load and circulating immune subsets (percentage of CD3+ T cell, CD3+ CD4+ T cells, CD3+ CD8+ T cells, CD19+ B cells and CD56+ NK cells) were analyzed by real-time PCR and flow cytometry. Patient age correlated negatively with CD3+ T cells (r=-0.264, P=0.001) and positively with CD56+ NK cells (r=0.272, P=0.001). Pre-treatment plasma EBV DNA correlated negatively with CD19+ B cells (r=-0.223, P=0.009) and CD4/CD8 ratio (r=-0.177, P=0.047). Patients with low CD19+ B cell had poorer 5-year progression-free survival (PFS) (66.6 vs. 81.8%, P=0.036) and 5-year overall survival (OS) (70.5 vs. 81.5%, P=0.097) than patients with high CD19+ B cells. Low CD19+ B cells was identified as a negative prognostic factor for 5-year PFS (hazard ratio [HR] 0.487; P=0.040), but not for 5-year OS (HR 0.550; P=0.102) in multivariate analysis. Post-treatment plasma EBV DNA was the most important prognostic factor for 5-year PFS (HR 2.983; P=0.006) and 5-year OS (HR 3.927; P<0.001). This study demonstrates the clinical value of circulating CD19+ B cell measurements in NPC patients.
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Strain effect on the optical polarization properties of c-plane Al?.??Ga?.??N/GaN superlattices.
Opt Express
PUBLISHED: 03-26-2014
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A new approach to realize ultraviolet (UV) light emitting diodes (LEDs) is using AlN/GaN or AlxGa1-xN/GaN SL structure as active layers. Effect of a uniaxial strain on the degree of polarization (DOP) of Al0.26Ga0.74N/GaN superlattices (SLs) grown on c-plane sapphire substrates has been investigated. Compared with AlN/AlxGa1-xN quantum wells, the DOP of the light emission from Al0.26Ga0.74N/GaN SLs shows an opposite variation tendency with in-plane strain and quantum confinement. The results would be helpful to the structural design of c-plane deep-UV and UVA LEDs to enhance surface emission.
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Stimulated emission in GaN-based laser diodes far below the threshold region.
Opt Express
PUBLISHED: 03-26-2014
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We identify that the stimulated emission of GaN laser diodes (LDs) emerges far below the traditionally recognized threshold from both optical and electrical experiments. Below the threshold, the linear-polarized stimulated emission has been the dominating part of overall emission and closely related to resonant cavity. Its intensity increases super linearly with current while that of spontaneous emission increases almost linearly. Moreover, the separation of quasi-Fermi levels of electrons and holes across the active region has already exceeded the photon emission energy, namely, realized the population-inversion.
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Endogenous animal toxin-like human ?-defensin 2 inhibits own K(+) channels through interaction with channel extracellular pore region.
Cell. Mol. Life Sci.
PUBLISHED: 03-24-2014
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Human potassium channels are widely inhibited by peptide toxins from venomous animals. However, no human endogenous peptide inhibitor has been discovered so far. In this study, we demonstrate for the first time using electrophysiological techniques, that endogenous human ?-defensin 2 (hBD2) is able to selectively and dose-dependently inhibit the human voltage-gated Kv1.3 channel at picomolar peptide concentration. The co-immunoprecipitation assays further supported the selective binding of hBD2 to Kv1.3 channel. Using mutagenesis experiments, we found that the outer pore domain of Kv1.3 channel was the binding site of hBD2, which is similar to the interacting site of Kv1.3 channel recognized by animal toxin inhibitors. The hBD2 was able to suppress IL-2 production through inhibition of Kv1.3 channel currents in human Jurkat cells, which was further confirmed by the lack of hBD2 activity on IL-2 production after Kv1.3 knockdown in these cells. More interestingly, hBD2 was also found to efficiently inhibit Kv1.3 channel currents and suppress IL-2 production in both human primary CD3(+) T cells and peripheral mononuclear cells from either healthy donors or psoriasis patients. Our findings not only evidenced hBD2 as the first characterized endogenous peptide inhibitor of human potassium channels, but also paved a promising avenue to investigate newly discovered function of hBD2 as Kv1.3 channel inhibitor in the immune system and other fields.
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Pretreatment Epstein-Barr virus DNA load and cumulative cisplatin dose intensity affect long-term outcome of nasopharyngeal carcinoma treated with concurrent chemotherapy: experience of an institute in an endemic area.
Oncol Res Treat
PUBLISHED: 01-13-2014
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We retrospectively compared the long-term efficacy of concurrent chemoradiotherapy (CCRT) regimens (docetaxel vs. cisplatin), total dose intensity of cisplatin (> 200 vs. ? 200 mg/m2) and pretreatment plasma levels of Epstein-Barr virus (EBV) DNA for nasopharyngeal carcinoma (NPC), and investigated the prognostic factors.
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Pilot-symbols-aided cycle slip mitigation for DP-16QAM optical communication systems.
Opt Express
PUBLISHED: 10-10-2013
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A pilot-symbols-aided phase unwrapping (PAPU), which utilizes the time-division multiplexed pilot symbols that are transmitted with data, is proposed to do cycle slip detection and correction with the carrier phase estimation (CPE). Numerical simulations for 10 Gbaud dual-polarization 16-ary quadrature amplitude modulation (DP-16QAM) systems show that the block averaging quadrature phase-shift keying (QPSK) partitioning with PAPU greatly eliminates the performance degradation caused by cycle slips, maintains a low CS probability with less influence of filter length, and achieves a bit-error-rate (BER) performance below soft-decision forward error correction (FEC) limit 2 × 10?² at 15 dB optical signal-to-noise ratio with only 1.56% overhead and 6 MHz combined laser linewidth.
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Resonant absorption and scattering suppression of localized surface plasmons in Ag particles on green LED.
Opt Express
PUBLISHED: 06-06-2013
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The metallic-structure dependent localized surface plasmons (LSPs) coupling behaviors with InGaN QWs in a green LED epitaxial wafer are investigated by optical transmission, scanning electron microscopy (SEM) and photoluminescence (PL) measurements. Ag nanoparticles (NPs) are formed by thermal annealing Ag layer on the green LED wafer. SEM images show that for higher annealing temperature and/or thicker deposited Ag layer, larger Ag NPs can be produced, leading to the redshift of absorption peaks in the transmission spectra. Time resolved PL (TRPL) measurements indicate when LSP-MQW coupling occurs, PL decay rate is greatly enhanced especially at the resonant wavelength 560 nm. However, the PL intensity is suppressed by 3.5 folds compared to the bare LED. The resonant absorption and PL suppression are simulated by three dimension finite-difference-time-domain (FDTD), which suggests that Ag particle with smaller size and lower height lead to the larger dissipation of LSP.
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Performance improvement of GaN-based LEDs with step stage InGaN/GaN strain relief layers in GaN-based blue LEDs.
Opt Express
PUBLISHED: 04-11-2013
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The performance of nitride-based LEDs was improved by inserting dual stage and step stage InGaN/GaN strain relief layer (SRL) between the active layer and n-GaN template. The influences of step stage InGaN/GaN SRL on the structure, electrical and optical characteristics of GaN-based LEDs were investigated. The analysis of strain effect on recombination rate based k·p method indicated 12.5% reduction of strain in InGaN/GaN MQWs by inserting SRL with step stage InGaN/GaN structures. The surface morphology was improved and a smaller blue shift in the electroluminescence (EL) spectral with increasing injection current was observed for LEDs with step stage SRL compared with conventional LEDs. The output power of LEDs operating at 20 mA was about 15.3 mW, increased by more than 108% by using step stage InGaN/GaN SRL, which shows great potential of such InGaN/GaN SRL in modulating InGaN/GaN MQWs optical properties based on its strain relief function.
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Development of a phylogenetic tree model to investigate the role of genetic mutations in endometrial tumors.
Oncol. Rep.
PUBLISHED: 02-14-2011
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With the advancement of modern genome sequencing technology, thousands of genetic mutations have been identified in human tumors. However, analysis of the role of genetic mutations in tumor development is limited by the need for prevalence information among multiple tumors and by the lack of analytic capability to define the functional contribution of genetic mutations in patients, individually and collectively. To understand the genetic basis of human endometrial cancer, the fourth most common cancer in women, transcriptome sequencing was performed on an endometrial tumor paired with normal cervical tissue. Twenty-six non-synonymous somatic mutations were validated in the tumor genome. A phylogenetic tree illustrating the mutational time-line was developed based upon the distribution of 26 mutations in 30 randomly-selected laser-captured single cells from the tumor sections. Five ubiquitous mutations were identified that are presumed to occur in the cancer founder cell of the tumor, and may collectively play critical roles in endometrial oncogenesis. However, further testing in 10 additional endometrial tumors failed to show overlapping mutations in the cancer founder cells, indicating the lack of a single common oncogenic pathway for these endometrial tumors. The effects of individual mutations in cancer cell proliferation were calculated based on descendant cell number and time span since acquiring each mutation. We have developed a phylogenetic approach to characterize individual genetic mutations in cancer cell proliferation in a single resected patient tumor. This approach provides the capability to study the tumor-specific role of genetic mutations, without relying on prevalence information from other patients.
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Diffracted transmission effects of GaN and polymer two-dimensional square-lattice photonic crystals.
Opt Express
PUBLISHED: 04-03-2009
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The effects of the lattice pitch of GaN and polymer square-lattice photonic crystal (2PhC) on the diffracted transmission were studied by using rigorous coupled wave analysis (RCWA). Besides the first-order Bragg diffraction, higher-order diffractions from large pitches of PhC are also significant to the light extraction improvement. Three different diffraction mechanisms are illustrated through wave vector analysis. The enhancement factors of integrated transmission are obtained from a wide range of pitches with micro-scale for both GaN and polymer 2PhC. The experimental angular-resolved transmission on a transparent polymer sample of 2 microm pitch 2PhC is comparable to the simulation.
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Valence subband coupling effect on polarization of spontaneous emissions from Al-rich AlGaN/AlN quantum wells.
Opt Express
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The optical polarization properties of Al-rich AlGaN/AlN quantum wells (QWs) were investigated using the theoretical model based on the k·p method. Numerical results show that there is valence subband coupling which can influence the peak emission wavelength and emission intensity for TE and TM polarization components from Al-rich AlGaN/AlN QWs. Especially the valence subband coupling could be strong enough when CH1 is close to HH1 and LH1 subbands to modulate the critical Al content switching dominant emissions from TE to TM polarization. It is believed that the valence subband coupling may give important influence on polarization properties of spontaneous emissions and should be considered in designing high efficiency AlGaN-based ultraviolet (UV) LEDs.
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Valence band offset of ?-Ga2O3/wurtzite GaN heterostructure measured by X-ray photoelectron spectroscopy.
Nanoscale Res Lett
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A sample of the ?-Ga2O3/wurtzite GaN heterostructure has been grown by dry thermal oxidation of GaN on a sapphire substrate. X-ray diffraction measurements show that the ?-Ga2O3 layer was formed epitaxially on GaN. The valence band offset of the ?-Ga2O3/wurtzite GaN heterostructure is measured by X-ray photoelectron spectroscopy. It is demonstrated that the valence band of the ?-Ga2O3/GaN structure is 1.40?±?0.08 eV.
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Enhancement of surface emission in deep ultraviolet AlGaN-based light emitting diodes with staggered quantum wells.
Opt Lett
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The optical polarization properties of staggered AlGaN-AlGaN/AlN quantum wells (QWs) are investigated using the theoretical model based on the k·p method. The numerical results show that the energy level order and coupling relation of the valence subband structure change in the staggered QWs and the trend is beneficial to TE polarized transition compared to that of conventional AlGaN/AlN QWs. As a result, the staggered QWs have much stronger TE-polarized emission than conventional AlGaN-based QWs, which can enhance the surface emission of deep ultraviolet (DUV) light-emitting diodes (LEDs). The polarization control by using staggered QWs can be applied in high efficiency DUV AlGaN-based LEDs.
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Production of lipopeptides by Bacillus amyloliquefaciens XZ-173 in solid state fermentation using soybean flour and rice straw as the substrate.
Bioresour. Technol.
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This work was aimed to produce lipopeptides by Bacillus amyloliquefaciens XZ-173 in solid state fermentation using agro-industrial byproducts. A central composite design was used to get the highest lipopeptides production. Results revealed that the optimal conditions for maximum lipopeptides production were 1.79% starch and 1.91% yeast extract by employing 5.58 g soybean flour and 3.67 g rice straw as the solid substrate with initial pH 7.5, moisture content 55% and a 10% inoculum level at 30°C for 2 days. Under these conditions, the experimental yield of lipopeptides reached 50.01 mg/gds, which was very close to the predicted value (49.91 mg/gds). At high concentration, the lipopeptides extracted from fermented substrates showed strong antibiotic activity against Rhizoctonia solani and Ralstonia solanacearum and certain emulsification but good emulsion stability. This is the first report on lipopeptides production that uses rice straw as a major substrate.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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

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