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Find video protocols related to scientific articles indexed in Pubmed.
Sample-Averaged Biexciton Quantum Yield Measured by Solution-Phase Photon Correlation.
Nano Lett.
PUBLISHED: 11-20-2014
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The brightness of nanoscale optical materials such as semiconductor nanocrystals is currently limited in high excitation flux applications by inefficient multiexciton fluorescence. We have devised a solution-phase photon correlation measurement that can conveniently and reliably measure the average biexciton-to-exciton quantum yield ratio of an entire sample without user selection bias. This technique can be used to investigate the multiexciton recombination dynamics of a broad scope of synthetically underdeveloped materials, including those with low exciton quantum yields and poor fluorescence stability. Here, we have applied this method to measure weak biexciton fluorescence in samples of visible-emitting InP/ZnS and InAs/ZnS core/shell nanocrystals, and to demonstrate that a rapid CdS shell growth procedure can markedly increase the biexciton fluorescence of CdSe nanocrystals.
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Trade-offs of the opto-electrical properties of a-Si:H solar cells based on MOCVD BZO films.
Phys Chem Chem Phys
PUBLISHED: 11-20-2014
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Boron-doped zinc oxide (BZO) films, deposited by metal-organic chemical vapor deposition (MOCVD), have been widely used as front electrodes in thin-film solar cells due to their native pyramidal surface structure, which results in efficient light trapping. This light trapping effect can enhance the short-circuit current density (Jsc) of solar cells. However, nanocracks or voids in the silicon active layer may form when the surface morphology of the BZO is too sharp; this usually leads to degraded electrical properties of the cells, such as open-circuit voltage (Voc) and the fill factor (FF), which in turn decreases efficiency (Eff) [Bailat et al., Photovoltaic Energy Conversion, Conference Record of the 2006 IEEE 4th World Conference on. IEEE, 2006, vol. 2, pp. 1533-1536]. In this paper, an etching and coating method was proposed to modify the sharp "pyramids" on the surface of the BZO films. As a result, an evident enhancement was achieved for these modified, BZO-based cells' Voc, FF, and Eff, although the Jsc exhibited a small decrease. In order to increase the Jsc and maintain the improved electrical properties (Voc, FF) of the cell, a thin BZO coating, deposited by MOCVD, was introduced to coat the sputtering-treated BZO film. Finally, we optimized the trade-off among the Voc, FF, and Jsc, that is, we identified a regime with an increase of the Jsc as well as a further improvement of the other electrical properties.
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Complete Nucleotide Sequence of cfr-carrying IncX4 Plasmid, pSD11, from Escherichia coli.
Antimicrob. Agents Chemother.
PUBLISHED: 11-19-2014
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We report a complete nucleotide sequence of a plasmid carrying the multi-resistance gene cfr. This plasmid was isolated from an Escherichia coli strain of swine origin in 2011. This 37,672-bp plasmid, pSD11, had an IncX4 backbone similar to that of the IncX4 plasmids obtained from the USA and Australia, in which the cfr gene was flanked by two copies of IS26, and a truncated Tn1331 inserted.
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RAD6 promotes homologous recombination repair by activating the autophagy-mediated degradation of heterochromatin protein HP1.
Mol. Cell. Biol.
PUBLISHED: 11-12-2014
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Efficient DNA double-strand break (DSB) repair is critical for the maintenance of genome stability. Unrepaired or mis-repaired DSBs cause chromosomal rearrangements that can result in severe consequences such as tumorigenesis. RAD6 is an E2 ubiquitin-conjugating enzyme that plays a pivotal role in repairing UV-induced DNA damage. Here, we present evidence that RAD6 is also required for DNA DSB repair via homologous recombination (HR) by specifically regulating the degradation of heterochromatin protein 1? (HP1?). Our study indicates that RAD6 physically interacts with HP1? and ubiquitinates HP1? at residue K154, thereby promoting HP1? degradation through the autophagy pathway and eventually leading to an open chromatin structure that facilitates efficient HR DSB repair. Furthermore, bioinformatics studies have indicated that the expression of RAD6 and HP1? exhibits an inverse relationship and correlates with the survival rate of patients.
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l-Valine derived chiral N-sulfinamides as effective organocatalysts for the asymmetric hydrosilylation of N-alkyl and N-aryl protected ketimines.
Org. Biomol. Chem.
PUBLISHED: 11-08-2014
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l-Valine derived N-sulfinamides have been developed as efficient enantioselective Lewis basic organocatalysts for the asymmetric reduction of N-aryl and N-alkyl ketimines with trichlorosilane. Catalyst afforded up to 99% yield and 96% ee in the reduction of N-alkyl ketimines and up to 98% yield and 98% ee in the reduction of N-aryl ketimines.
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High-Efficiency Plasmon-Enhanced and Graphene-Supported Semiconductor/Metal Core-Satellite Hetero-Nanocrystal Photocatalysts for Visible-Light Dye Photodegradation and H2 Production from Water.
ACS Appl Mater Interfaces
PUBLISHED: 11-05-2014
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Solar-driven photocatalytic process based on electron-hole pair production in semiconductors is a long sought-after solution to a green and renewable energy and has attracted a renaissance of interest recently. The relatively low photocatalytic efficiency, however, is a main obstacle to their practical applications. A promising attempt to solve this problem is by combined use of metal nanoparticles, by taking advantage of strong and localized plasmonic near-field to enhance solar absorption and to increase the electron-hole pair generation rate at the surface of semiconductor. Here, we report a semiconductor/metal visible-light photocatalyst based on CdSe/CdS-Au (QD-Au) core-satellite heteronanocrystals, and assemble them on graphene nanosheets for better photocatalytic reaction. The as-synthesized photocatalyst exhibits excellent plasmon-enhanced photocatalytic activities toward both photodegradation of organic dye and visible-light H2 generation from water. The H2 evolution rate achieves a maximum of 3113 ?mol h(-1) g(-1) for the heteronanocrystal-graphene composites, which is about 155% enhancement compared to nonplasmonic QD-G sample and 340% enhancement compared to control QD-Au-G sample, and the apparent quantum efficiency (QE) reaches to 25.4% at wavelength of 450 nm.
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[Laser microdissection and mass spectrometry based proteomics in the diagnosis of kidney diseases].
Sheng Wu Gong Cheng Xue Bao
PUBLISHED: 10-28-2014
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In recent years, laser microdissection followed by mass spectrometry (LMD/MS) has been successfully applied to the proteomic studies of formalin-fixed paraffin-embedded (FFPE) renal tissues. This new technique improves the diagnosis of kidney diseases and has a better potential for future clinical application. The review focuses on the use of this methodology for exploring the mechanisms, diagnosis and classification of kidney diseases including renal amyloidosis and membrane proliferative glomerulonephritis.
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[A pilot study of establishing course of professional English on stomatology].
Shanghai Kou Qiang Yi Xue
PUBLISHED: 10-24-2014
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The importance of specialized English on stomatology is becoming more and more significant under the new situation. It used to be focused on vocabulary and literature teaching in the original course of specialized English, which was lack of practicability. Thus, we try to establish a course of professional English on stomatology during the postgraduate stage of the seven-year students in our college, in order to complement the course of specialized English on stomatology and improve the students' practical ability to use specialized English. In this paper, the teaching content and method, teaching materials setting and the feedback from students on the course were discussed and analyzed, in order to lay a foundation for better construction of the course.
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Advances in Techniques for Probing Mechanoregulation of Tissue Morphogenesis.
J Lab Autom
PUBLISHED: 10-22-2014
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Cells process various mechanical cues in the microenvironment to self-organize into high-order architectures during tissue morphogenesis. Impairment of morphogenic processes is the underlying cause of many diseases; as such, understanding the regulatory mechanisms associated with these processes will form the foundation for the development of innovative approaches in cell therapy and tissue engineering. Nevertheless, little is known about how cells collectively respond to mechanical cues in the microenvironment, such as global geometric guidance, local cell-cell interactions, and other physicochemical factors, for the emergence of the structural hierarchy across multiple length scales. To elucidate the mechanoregulation of tissue morphogenesis, numerous approaches based on biochemical, biomaterial, and biophysical techniques have been developed in the past decades. In this review, we summarize techniques and approaches for probing the mechanoregulation of tissue morphogenesis and illustrate their applications in vasculature development. The potential and limitations of these methods are also discussed with a view toward the investigation of a wide spectrum of tissue morphogenic processes.
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?-apo-13-Carotenone Regulates Retinoid X Receptor Transcriptional Activity Through Tetramerization of the Receptor.
J. Biol. Chem.
PUBLISHED: 10-18-2014
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Retinoid X receptor (RXRa) is activated by 9-cis-retinoic acid (9cRA) and regulates transcription as a homodimer or as a heterodimer with other nuclear receptors. We have previously demonstrated that beta-apo-13-carotenone, an eccentric cleavage product of bea-carotene, antagonizes the activation of RXRa by 9cRA in mammalian cells overexpressing this receptor. However, the molecular mechanism of beta-apo-13-carotenone modulation on RXRa transcriptional activity is not understood and is the subject of this report. We performed transactivation assays using full length RXRa and reporter gene constructs (RXRE-Luc) transfected into COS-7 cells and luciferase activity was examined. beta-apo-13-Carotenone was compared with the RXR? antagonist UVI 3003. The results showed that both beta-apo-13-carotenone and UVI 3003 shifted the dose-dependent RXRa activation by 9cRA. In contrast, results of assays using a hybrid Gal4-DBD:RXRa-LBD receptor reporter cell assay that detects 9cRA-induced coactivator binding to the ligand binding domain demonstrated that UVI3003 significantly inhibited 9cRA-induced coactivator binding to RXR?LBD, but beta-apo-13-carotenone did not. However, both beta-apo-13-carotenone and UVI 3003 inhibited 9-cRA induction of caspase 9 gene expression in the mammary carcinoma cell line MCF7. In order to resolve this apparent contradiction we investigated the effect of beta-apo-13-carotenone on the oligomeric state of purified recombinant RXRa LBD. beta-apo-13-carotenone induces tetramerization of the RXRaLBD whereas UVI3003 had no effect on the oligomeric state. These observations suggest that beta-apo-13-carotenone regulates RXRa transcriptional activity through inducing the formation of the transcriptionally silent RXRa tetramer.
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A Randomized, Three-arm Study to Optimize Lamivudine Efficacy in HBeAg Positive Chronic Hepatitis B Patients.
J. Gastroenterol. Hepatol.
PUBLISHED: 10-14-2014
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To compare the efficacy at week 104 of lamivudine monotherapy (MONO), lamivudine plus adefovir dipivoxil (ADV) combination therapy (COMBO), and lamivudine optimization strategy (OPTIMIZE).
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Clinical characteristics of human infection with a novel avian-origin influenza A(H10N8) virus.
Chin. Med. J.
PUBLISHED: 10-01-2014
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Novel influenza A viruses of avian-origin may be the precursors of pandemic strains. This descriptive study aims to introduce a novel avian-origin influenza A (H10N8) virus which can infect humans and cause severe diseases.
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Antioxidant and nitrite-scavenging capacities of phenolic compounds from sugarcane (Saccharum officinarum L.) tops.
Molecules
PUBLISHED: 08-26-2014
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Sugarcane tops were extracted with 50% ethanol and fractionated by petroleum ether, ethyl acetate (EtOAc), and n-butyl alcohol successively. Eight phenolic compounds in EtOAc extracts were purified through silica gel and Sephadex LH-20 column chromatographies, and then identified by nuclear magnetic resonance and electrospray ionization mass spectra. The results showed that eight phenolic compounds from EtOAc extracts were identified as caffeic acid, cis-p-hydroxycinnamic acid, quercetin, apigenin, albanin A, australone A, moracin M, and 5'-geranyl-5,7,2',4'-tetrahydroxyflavone. The antioxidant and nitrite-scavenging capacities of different solvent extracts correlated positively with their total phenolic (TP) contents. Amongst various extracts, EtOAc extracts possessed the highest TP content and presented the strongest oxygen radical absorbance capacity (ORAC), 1,1'-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging capacity, 2,2'-azobis-3-ethylbenthiaazoline-6-sulfonic acid (ABTS) radical-scavenging capacity, ferric reducing antioxidant power (FRAP) and nitrite-scavenging capacity. Thus, sugarcane tops could be promoted as a source of natural antioxidant.
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Genetic landscape of esophageal squamous cell carcinoma.
Nat. Genet.
PUBLISHED: 08-24-2014
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Esophageal squamous cell carcinoma (ESCC) is one of the deadliest cancers. We performed exome sequencing on 113 tumor-normal pairs, yielding a mean of 82 non-silent mutations per tumor, and 8 cell lines. The mutational profile of ESCC closely resembles those of squamous cell carcinomas of other tissues but differs from that of esophageal adenocarcinoma. Genes involved in cell cycle and apoptosis regulation were mutated in 99% of cases by somatic alterations of TP53 (93%), CCND1 (33%), CDKN2A (20%), NFE2L2 (10%) and RB1 (9%). Histone modifier genes were frequently mutated, including KMT2D (also called MLL2; 19%), KMT2C (MLL3; 6%), KDM6A (7%), EP300 (10%) and CREBBP (6%). EP300 mutations were associated with poor survival. The Hippo and Notch pathways were dysregulated by mutations in FAT1, FAT2, FAT3 or FAT4 (27%) or AJUBA (JUB; 7%) and NOTCH1, NOTCH2 or NOTCH3 (22%) or FBXW7 (5%), respectively. These results define the mutational landscape of ESCC and highlight mutations in epigenetic modulators with prognostic and potentially therapeutic implications.
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Sevoflurane postconditioning attenuates cerebral ischemia-reperfusion injury via protein kinase B/nuclear factor-erythroid 2-related factor 2 pathway activation.
Int. J. Dev. Neurosci.
PUBLISHED: 08-19-2014
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Oxidative damage plays a critical role in many diseases of the central nervous system. This study was conducted to determine the molecular mechanisms involved in the putative anti-oxidative effects of sevoflurane against experimental stroke. Focal cerebral ischemia was performed via 1h of middle cerebral artery occlusion followed by reperfusion. At the onset of reperfusion, rats were subjected to postconditioning with sevoflurane or without sevoflurane for 1h. Neurological deficit score was assessed at different time points after reperfusion. Cerebral infarct volume, oxidative stress level and the binding activity of Nrf2 to antioxidant response element were assessed, meanwhile the expression of nuclear factor-erythroid 2-related factor 2 (Nrf2), quinine oxidoreductase 1 (NQO1), protein kinase B (Akt) and phosphor-Akt was examined by Western blot at 72h after reperfusion. Sevoflurane postconditioning administration significantly reduced neurological deficit score, infarct volume and oxidative stress levels, while increased the expression of phosphorylation Akt, NQO1, Nrf2 and the binding activity of Nrf2 to ARE in middle cerebral artery occlusion rats. These neuroprotective effects were all suppressed by LY294002, a selective PI3K blocker. Taken together, these findings provided evidence that sevoflurane postconditioning protects brain against ischemic/reperfusion injury, and this neuroprotective effect involves the Akt/Nrf2 pathway.
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Caspase-3 inhibition prevents the development of hepatopulmonary syndrome in common bile duct ligation rats by alleviating pulmonary injury.
Liver Int.
PUBLISHED: 08-11-2014
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Common bile duct ligation (CBDL) rats is an accepted experimental model of hepatopulmonary syndrome (HPS), defined as liver disease and intrapulmonary vascular dilatation and hypoxaemia. Pulmonary Akt and ERK activation followed by angiogenesis in the later stages of CBDL, contribute to the pathogenesis of HPS. However, the mechanisms behind Akt and ERK activation remain undefined. Pulmonary injury induced by increased bilirubin, endotoxin and inflammatory mediators occurs in the early stages of CBDL. We assessed the effects of relieving pulmonary injury on Akt and ERK activation and on the development of HPS following CBDL.
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Label-free quantitative detection of tumor-derived exosomes through surface plasmon resonance imaging.
Anal. Chem.
PUBLISHED: 08-11-2014
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Exosomes are endosome-derived membrane vesicles carrying proteins and nucleic acids that are involved in cellular functions such as intercellular communication, protein and RNA secretion, and antigen presentation. Therefore, exosomes serve as potential biomarkers for many diseases including cancer. Because exosomes are difficult to enrich or purify from biofluids, quantification of exosomes is tedious and inaccurate. Here, we present a real-time, label-free, and quantitative method to detect and characterize tumor-derived exosomes without enrichment or purification. Utilizing surface plasmon resonance imaging (SPRi) in combination with antibody microarrays specific to the extracellular domains of exosome membrane proteins, exosomes in tumor cell culture medium can be quantitatively detected. We found a positive correlation between the metastatic potential of tumor cell lines and exosome secretion. This method provides an easy, efficient, and novel way to detect exosome secretion and thus an avenue toward the diagnosis and prognosis prediction of cancer.
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Association between Vitamin D level and viral load or fibrosis stage in chronic hepatitis B patients from Southern China.
J. Gastroenterol. Hepatol.
PUBLISHED: 08-05-2014
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The role vitamin D playing in patients with chronic hepatitis C has been intensively studied. However, studies on the potential interaction between vitamin D level and chronic hepatitis B are still limited. This study aimed to explore whether any association existed between serum vitamin D level and liver histology or virological parameters in patients with chronic hepatitis B infection in Southern China.
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A time course study about gene expression of post-thermal injury with DNA microarray.
Int. J. Dermatol.
PUBLISHED: 07-30-2014
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Burn injury is one of the most common and devastating forms of trauma in daily life. However, the exact sequence of events after burn injury remains unknown.
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A flexible pinhole camera model for coherent nonuniform sampling.
IEEE Comput Graph Appl
PUBLISHED: 07-23-2014
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The flexible pinhole camera (FPC) allows flexible modulation of the sampling rate over the field of view. The FPC is defined by a viewpoint and a map specifying the sampling locations on the image plane. The map is constructed from known regions of interest with interactive and automatic approaches. The FPC provides inexpensive 3D projection that allows rendering complex datasets quickly, in feed-forward fashion, by projection followed by rasterization. The FPC supports many types of data, including image, height field, geometry, and volume data. The resulting image is a coherent nonuniform sampling (CoNUS) of the dataset that matches the local variation of the dataset's importance. CoNUS images have been successfully implemented for remote visualization, focus-plus-context visualization, and acceleration of expensive rendering effects such as surface geometric detail and specular reflection. A video explaining and demonstrating the FPC is at http://youtu.be/kvFe5XjOPNM.
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[Study on extraction process of coumarin in a Mongolian drug Chagan-sorlo (Radix Glehniae)].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 07-11-2014
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The present paper discusses ultrasonic extraction method aided extraction of coumarin from a Mongolian drug, Chagan-sorlo (Radix Glehniae), aiming to study out how much coumarin contained in Chagan-sorlo, and to provide the scientific basis and production guidance for extracting coumarin from Chagan-sorlo. Under different conditions the coumarin in Chagan-sorlo was extracted by ultrasonic, measured and analyzed, and then HPLC was used to carry out the measurement. Result showed that with solvent volume fraction of 70%, extraction time of 20 min, ultrasonic power of 175 W, temperature of 25 degrees C, solid-liquid ratio of 1 : 20, and 80-100 mesh extraction, the coumarin extraction reaches the highest yield.
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Expression of matrix Gla protein and osteocalcin in the developing tibial epiphysis of mice.
Histol. Histopathol.
PUBLISHED: 06-24-2014
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This study aimed to investigate the expression of matrix Gla protein (MGP) and osteocalcin (OCN) in the tibial epiphysis of developing mice. At 1, 2, 3, and 4 weeks after birth, tibiae were removed and processed for histochemical observations and western blot analyses under anesthesia. To evaluate bone volume, the specimens were scanned with Micro CT Scanner from the articular cartilage through the growth plate, along the long axis of tibia. At 1 week after birth, OCN reactivity was faint in the region of vascular invasion, while hardly any MGP reactivity was discernible. Subsequently, MGP reactivity was seen on the cartilaginous lacunar walls of hypertrophic chondrocytes, while OCN reactivity was evenly found not only in the bone matrix, but also in the cartilaginous lacunar walls and on the bone surfaces. Furthermore, double-immunostaining clearly showed that MGP reactivity appeared closer to the cartilage matrix than OCN reactivity until postnatal week 3. Interestingly, the immunoreactivities for MGP and OCN both showed tidemarks in the articular cartilage at postnatal week 4, and MGP reactivity was more intense than OCN reactivity. Statistical analyses showed an overall upward trend in MGP and OCN expression levels during tibial epiphysis development, even though OCN was more abundant than MGP at every time-point. Taken together, our findings suggest that the expression of MGP and OCN increased gradually in the murine developing tibial epiphysis, and the two mineral-associated proteins may occur at the same location during a particular period, but at different levels.
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Assessment of density gradient centrifugation (DGC) and sperm chromatin dispersion (SCD) measurements in couples with male factor infertility undergoing ICSI.
J. Assist. Reprod. Genet.
PUBLISHED: 06-15-2014
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To investigate how effectively density gradient centrifugation (DGC) improves sperm nuclear integrity and to determine whether the sperm chromatin dispersion (SCD) test of sperm nuclear integrity in native or DGC-treated semen can predict the outcome of assisted reproductive technology (ART) in couples undergoing intracytoplasmic sperm injection (ICSI).
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Primary diffuse large B-cell lymphoma of the ovary is of a germinal centre B-cell-like phenotype.
Virchows Arch.
PUBLISHED: 06-14-2014
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Primary ovarian lymphoma is rare. To better understand the clinicopathological and molecular features of these tumours, we studied 14 patients (age range 13 to 74 years, mean 46.9 years) with non-Hodgkin's lymphoma who initially presented with an ovarian tumour. The clinicopathological features were reviewed and tissue samples were studied by immunohistochemistry and for immunoglobulin gene rearrangement, presence of Epstein Barr virus and for MYC and BCL-2 rearrangements by fluorescence in situ hybridisation. The most common symptoms were abdominal pain and abdominal distension. Ten patients had a unilateral (7 left, 3 right) ovarian mass and 4 had bilateral ovarian masses, size range 4 to 13 cm (mean, 7.9 cm). Of the 14 lymphomas, 12 were classified as diffuse large B-cell lymphoma (DLBCL) and 2 as Burkitt lymphoma. The Burkitt lymphomas had a MYC rearrangement. The DLBCLs were of the germinal centre B-cell-like subtype. One DLBCL patient had MYC and BCL2 rearrangements. The treatment consisted of various combinations of surgery, chemotherapy and radiotherapy. The follow-up period ranged from 3 to 56 months. During the follow-up period, 8 patients died of disease, 4 were alive with disease, and 2 were alive without disease. Most primary ovarian lymphomas are of germinal centre B-cell-like subtype DLBCL, which have high proliferative activity and poor prognosis.
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An NN-based SRD decomposition algorithm and its application in nonlinear compensation.
Sensors (Basel)
PUBLISHED: 06-04-2014
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In this study, a neural network-based square root of descending (SRD) order decomposition algorithm for compensating for nonlinear data generated by sensors is presented. The study aims at exploring the optimized decomposition of data 1.00,0.00,0.00 and minimizing the computational complexity and memory space of the training process. A linear decomposition algorithm, which automatically finds the optimal decomposition N and reduces the training time to 1/?N and memory cost to 1/N has been implemented on nonlinear data obtained from an encoder. Particular focus is given to the theoretical access of estimating the numbers of hidden nodes and the precision of varying the decomposition method. Numerical experiments are designed to evaluate the effect of this algorithm. Moreover, a designed device for angular sensor calibration is presented. We conduct an experiment that samples the data of an encoder and compensates for the nonlinearity of the encoder to testify this novel algorithm.
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Histological Evidence of Increased Osteoclast Cell Number and Asymmetric Bone Resorption Activity in the Tibiae of Interleukin-6-Deficient Mice.
J. Histochem. Cytochem.
PUBLISHED: 05-14-2014
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Interleukin-6 (IL-6) is a multifunctional cytokine considered to modulate bone homeostasis. Based on previous contradictory studies, we aimed to verify the influence of IL-6 deficiency on bone remodeling using an IL-6 knockout (IL-6-/-) murine model. Eight-month-old male mice, homozygous for the disrupted IL-6 gene, and their wild type (WT) littermates (control), were used. After transcardiac perfusion, tibiae were removed for histochemical analysis. Compared with the control group, IL-6 deficiency increased tartrate resistant acid phosphatase (TRAP)-positive osteoclast numbers and up-regulated the alkaline phosphatase (ALP) activity of osteoblasts in the metaphysis of the tibia. However, further analysis of serial histological sections from IL-6-/- mice found a significant discrepancy in osteoclast number, with the higher number of TRAP-positive osteoclasts conflicting with the lower number of cathepsin K-positive osteoclasts. Moreover, TUNEL staining identified a significantly higher rate of osteoclast apoptosis in IL-6-/- mice as compared with their WT controls. IL-6 deficiency induced abundant TRAP-positive osteoclasts but delayed bone remodeling by significantly inhibiting the bone resorption activity of osteoclasts and promoting osteoclast apoptosis.
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[Research on optimization of mathematical model of flow injection-hydride generation-atomic fluorescence spectrometry].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 05-03-2014
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Flow injection-hydride generation-atomic fluorescence spectrometry was a widely used method in the industries of health, environmental, geological and metallurgical fields for the merit of high sensitivity, wide measurement range and fast analytical speed. However, optimization of this method was too difficult as there exist so many parameters affecting the sensitivity and broadening. Generally, the optimal conditions were sought through several experiments. The present paper proposed a mathematical model between the parameters and sensitivity/broadening coefficients using the law of conservation of mass according to the characteristics of hydride chemical reaction and the composition of the system, which was proved to be accurate as comparing the theoretical simulation and experimental results through the test of arsanilic acid standard solution. Finally, this paper has put a relation map between the parameters and sensitivity/broadening coefficients, and summarized that GLS volume, carrier solution flow rate and sample loop volume were the most factors affecting sensitivity and broadening coefficients. Optimizing these three factors with this relation map, the relative sensitivity was advanced by 2.9 times and relative broadening was reduced by 0.76 times. This model can provide a theoretical guidance for the optimization of the experimental conditions.
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[Effect of early enteral nutrition on immune response and clinical outcomes after esophageal cancer surgery].
Zhonghua Wei Chang Wai Ke Za Zhi
PUBLISHED: 04-25-2014
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To evaluate the effect of early enteral nutrition(EEN) on immune response and clinical outcomes after esophageal cancer operation.
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Hierarchical structure and mechanical properties of remineralized dentin.
J Mech Behav Biomed Mater
PUBLISHED: 04-10-2014
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It is widely accepted that the mechanical properties of dentin are significantly determined by its hierarchical structure. The current correlation between the mechanical properties and the hierarchical structure was mainly established by studying altered forms of dentin, which limits the potential outcome of the research. In this study, dentins with three different hierarchical structures were obtained via two different remineralization procedures and at different remineralization stages: (1) a dentin structure with amorphous minerals incorporated into the collagen fibrils, (2) a dentin with crystallized nanominerals incorporated into the collagen fibrils, and (3) a dentin with an out-of-order mineral layer filling the collagen fibrils matrix. Nanoindentation tests were performed to investigate the mechanical behavior of the remineralized dentin slides. The results showed that the incorporation of the crystallized nanominerals into the acid-etched demineralized organic fibrils resulted in a remarkable improvement of the mechanical properties of the dentin. In contrast, for the other two structures, i.e. the amorphous minerals inside the collagen fibrils and the out-of-order mineral layer within the collagen fibrils matrix, the excellent mechanical properties of dentin could not be restored.
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[Diagnostic value of contrast-enhanced ultrasonography in preoperative Borrmann classification of gastric cancer].
Zhonghua Wei Chang Wai Ke Za Zhi
PUBLISHED: 03-28-2014
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To investigate the diagnostic value of contrast-enhanced ultrasonography (CEUS) in preoperative Borrmann classification of gastric cancer.
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Maxillary pain is the first indication of the presence of multiple myeloma: A case report.
Mol Clin Oncol
PUBLISHED: 03-21-2014
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Multiple myeloma is a primary malignancy of bone marrow characterized by the clonal proliferation of plasma cells and production of monoclonal immunoglobulin. The disease occurs more frequently in males, with the average age at diagnosis being ?60 years. The first manifestation of multiple myeloma is varied and depends on the sites and extent of involvement. The predominant clinical symptoms of multiple myeloma are associated with bone pain and renal dysfunction. Neoplastic cells usually produce large amounts of monoclonal immunoglobulin light or heavy chains that can be detected in serum or urine, while plasmacytoma may be identified on marrow biopsy. The present study reported on the case of a 69-year-old male patient presenting with a complaint of a painful lesion in the left maxilla. Physical examination, imaging, laboratory investigations and biopsy were conducted, confirming the diagnosis of multiple myeloma. The results obtained suggest that the dentist should address oral manifestations as first indications of multiple myeloma.
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Long-term atmospheric wet deposition of dissolved organic nitrogen in a typical red-soil agro-ecosystem, Southeastern China.
Environ Sci Process Impacts
PUBLISHED: 03-20-2014
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Dissolved organic nitrogen (DON) from atmospheric deposition has been a growing concern in the world and atmospheric nitrogen (N) deposition is increasing quickly in China especially Southeastern China. In our study, DON wet deposition was estimated by collecting and analyzing rainwater samples continuously over eight years (2005-2012) in a typical red-soil farmland ecosystem, Southeast China. Results showed that the volume-weighted-average DON concentration varied from 0.2 to 3.3 mg N L(-1) with an average of 1.2 mg N L(-1). DON flux ranged from 5.7 to 71.6 kg N ha(-1) year(-1) and averaged 19.7 kg N ha(-1) year(-1) which accounted for 34.6% of the total dissolved nitrogen (TDN) in wet deposition during the eight-year period. Analysis of DON concentration and flux, contribution of DON to TDN, rainfall, rain frequency, air temperature and wind frequency and the application of pig manure revealed possible pollution sources. Significant positive linear relation of annual DON flux and usage of pig manure (P<0.0001) suggested that agricultural activities, especially application of pig manure, were the main source of DON in the study area. In conclusion, DON wet deposition was an important part of TDN and would have a possible effect on N cycle in the red-soil agro-ecosystem in the future.
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Novel structural phases and superconductivity of iridium telluride under high pressures.
Sci Rep
PUBLISHED: 03-13-2014
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Transition metal selenide and telluride have recently receive considerable attention due to their possible structural relation to ferropnictide. Pressure is often used as an efficient way to modify the crystal or electronic structure that in many cases lead to new material states of interest. Here we search the structures of IrTe2 up to 150 GPa using crystal structure prediction techniques combining with ab initio calculations. Three new stable phases under high pressures are predicted, and their electronic structure properties, phonon spectra, and electron-phonon couplings are also investigated. Significant reconstructions of band structures and Fermi surfaces are found in these new phases. Calculated results show that while the C2/m-2 phase has bad metal behavior and very weak electron-phonon coupling, the and I4/mmm phases have relatively higher electron-phonon coupling up to ~ 1.5 and 0.7, respectively. The variable-composition searching have been performed, newly compounds with different stoichiometries, such as IrTe3, IrTe, and Ir3Te, are predicted to be thermodynamically and dynamically stable at high pressures. The pressure range investigated here is accessible in the diamond anvil cell experiments, thus our results might stimulate further experimental studies.
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Magneto-fluorescent core-shell supernanoparticles.
Nat Commun
PUBLISHED: 03-12-2014
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Magneto-fluorescent particles have been recognized as an emerging class of materials that exhibit great potential in advanced applications. However, synthesizing such magneto-fluorescent nanomaterials that simultaneously exhibit uniform and tunable sizes, high magnetic content loading, maximized fluorophore coverage at the surface and a versatile surface functionality has proven challenging. Here we report a simple approach for co-assembling magnetic nanoparticles with fluorescent quantum dots to form colloidal magneto-fluorescent supernanoparticles. Importantly, these supernanoparticles exhibit a superstructure consisting of a close-packed magnetic nanoparticle 'core', which is fully surrounded by a 'shell' of fluorescent quantum dots. A thin layer of silica coating provides high colloidal stability and biocompatibility, and a versatile surface functionality. We demonstrate that after surface pegylation, these silica-coated magneto-fluorescent supernanoparticles can be magnetically manipulated inside living cells while being optically tracked. Moreover, our silica-coated magneto-fluorescent supernanoparticles can also serve as an in vivo multi-photon and magnetic resonance dual-modal imaging probe.
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Cardiovascular responses to heat stress in chronic heart failure.
Curr Heart Fail Rep
PUBLISHED: 03-07-2014
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Clinical reports have suggested that patients with heart diseases may be particularly vulnerable to heat injury. This review examines the effects of heat stress on cardiovascular and autonomic functions in patients with chronic heart failure (CHF). Laboratory investigations have shown that cutaneous vasodilator responses to heating are impaired in patients, whereas activation of skin sympathetic nerve activation is not attenuated in CHF as compared to controls. Attenuated cutaneous vasodilation may increase the risk of a heat related illness when CHF subjects are exposed to hyperthermic conditions.
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PA-1, a novel synthesized pyrrolizidine alkaloid, inhibits the growth of Escherichia coli and Staphylococcus aureus by damaging the cell membrane.
J. Antibiot.
PUBLISHED: 03-04-2014
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In the present study, antimicrobial activity and mode of a novel synthesized pyrrolizidine alkaloid (PA-1) were investigated. PA-1 exhibited predominantly strong antibacterial activity toward six bacteria tested with minimal inhibitory concentration (MIC) values ranging from 0.0039 to 0.025?mg?ml(-1). The time-kill assay indicated that PA-1 killed Escherichia coli and Staphylococcus aureus completely at 2MIC (minimum bactericidal concentration) within 8?h. Besides, PA-1-induced death rates of most sensitive strains (E. coli, 97.80% and S. aureus, 96.24%) were analyzed by flow cytometry. A combination of approaches was used to verify the membrane damage of E. coli and S. aureus. Results showed that release of 260?nm absorbing materials quickly increased after PA-1 treatment. PA-1 also rapidly promoted the uptake of crystal violet from 24.52 to 97.12% for E. coli and from 19.68 to 97.63% for S. aureus when the concentrations were changed from MIC to 4MIC. Furthermore, the cellular membrane damages were testified by the significant increase of fluorescence intensity and decrease of membrane potential. Finally, lecithin and phosphate groups were applied to search the possibly targets on the cytoplasmic membrane. Results showed that PA-1 acted on cytoplasmic membrane phospholipids and phosphate groups of S. aureus but not of E. coli. In conclusion, the novel synthesized PA-1 exerted its antibacterial activity by acting on membrane phospholipids and phosphate groups and then damaging the structures of cellular membrane, which finally led to cell death.
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An adaptive data collection algorithm based on a Bayesian compressed sensing framework.
Sensors (Basel)
PUBLISHED: 03-02-2014
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For Wireless Sensor Networks, energy efficiency is always a key consideration in system design. Compressed sensing is a new theory which has promising prospects in WSNs. However, how to construct a sparse projection matrix is a problem. In this paper, based on a Bayesian compressed sensing framework, a new adaptive algorithm which can integrate routing and data collection is proposed. By introducing new target node selection metrics, embedding the routing structure and maximizing the differential entropy for each collection round, an adaptive projection vector is constructed. Simulations show that compared to reference algorithms, the proposed algorithm can decrease computation complexity and improve energy efficiency.
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Boron trifluoride etherate functioning as a fluorine source in an iodosobenzene-mediated intramolecular aminofluorination of homoallylic amines.
Org. Lett.
PUBLISHED: 02-26-2014
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A widely used Lewis acid BF3·Et2O was shown to be capable of acting as an efficient fluorinating agent in an intramolecular aminofluorination reaction of homoallylic amines to provide 3-fluoropyrrolidines mediated by a commercially available hypervalent iodine(III) reagent PhIO at room temperature. A mechanism involving a carbocation intermediate was proposed on the basis of several experimental evidence.
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Design and synthesis of thiazole derivatives as potent FabH inhibitors with antibacterial activity.
Eur J Med Chem
PUBLISHED: 02-25-2014
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Components of fatty acid biosynthetic pathway have been identified as attractive targets for the development of new antibacterial agents. Compounds of series A (4a-4 g) and series B (5a-5 g) were synthesized by the formation of an amine bond between aromatic acid and 4-phenylthiazol-2-amine or 4-(4-bromophenyl)thiazol-2-amine. These thiazole derivatives have evaluated as potent FabH inhibitors. Nineteen compounds (4b-4h, 4 k, 4 l, 5a-5h, 5k, 5l) are reported for the first time. Most of the synthesized compounds exhibited antibacterial activity in the MTT assay. The MIC value of these compounds ranged from 1.56 ?g/mL to 100 ?g/mL. Moreover, the tested compounds also showed FabH inhibition ability with IC50 value ranging from 5.8 ?M to 48.1 ?M. The IC50 values are near the MIC values. Compound 5f has exhibited the best antibacterial and Escherichia coli FabH inhibitory activity. Docking simulation and the QSAR study was conducted for learning about binding mode and the relationship between structure and activity.
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Bone marrow vascular niche: home for hematopoietic stem cells.
Bone Marrow Res
PUBLISHED: 02-13-2014
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Though discovered later than osteoblastic niche, vascular niche has been regarded as an alternative indispensable niche operating regulation on hematopoietic stem cells (HSCs). As significant progresses gained on this type niche, it is gradually clear that the main work of vascular niche is undertaking to support hematopoiesis. However, compared to what have been defined in the mechanisms through which the osteoblastic niche regulates hematopoiesis, we know less in vascular niche. In this review, based on research data hitherto we will focus on component foundation and various functions of vascular niche that guarantee the normal hematopoiesis process within bone marrow microenvironments. And the possible pathways raised by various research results through which this environment undergoes its function will be discussed as well.
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A two-enzyme immobilization approach using carbon nanotubes/silica as support.
Biotechnol. Prog.
PUBLISHED: 01-28-2014
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Multiple enzyme mixtures are attractive for the production of many compounds at an industrial level. We report a practical and novel approach for coimmobilization of two enzymes. The system consists of a silica microsphere core coated with two layers of individually immobilized enzymes. The model enzymes ?-amylase (AA) and glucoamylase (GluA) were individually immobilized on carbon nanotubes (CNTs). A CNT-GluA layer was formed by adsorbing CNT-GluA onto silica microsphere. A sol-gel layer with entrapped CNT-AA was then formed outside the CNT-GluA/silica microsphere conjugate. The coimmobilized ?-amylase and glucoamylase exhibited 95.1% of the activity of the mixture of free ?-amylase and glucoamylase. The consecutive use exhibited a good stability of the coimmobilized enzymes. The developed approach demonstrates advantages, including controlling the ratio of coimmobilized enzymes in an easy way, facilitating diffusion of small molecules in and out of the matrix, and preventing the leaching of enzymes. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 2014.
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Mechanical Pleurodesis Does Not Reduce Recurrence of Spontaneous Pneumothorax: A Randomized Trial.
Ann. Thorac. Surg.
PUBLISHED: 01-27-2014
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Mechanical pleurodesis is widely used to treat primary spontaneous pneumothorax to decrease postoperative recurrence after thoracoscopic bullectomy, but it is unclear whether it actually reduces primary spontaneous pneumothorax recurrence. We aimed to investigate the effectiveness of mechanical pleurodesis after thoracoscopic treatment of primary spontaneous pneumothorax.
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TIPE3 Is the Transfer Protein of Lipid Second Messengers that Promote Cancer.
Cancer Cell
PUBLISHED: 01-24-2014
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More than half of human cancers have aberrantly upregulated phosphoinositide signals; yet how phospholipid signals are controlled during tumorigenesis is not fully understood. We report here that TIPE3 (TNFAIP8L3) is the transfer protein of phosphoinositide second messengers that promote cancer. High-resolution crystal structure of TIPE3 shows a large hydrophobic cavity that is occupied by a phospholipid-like molecule. TIPE3 preferentially captures and shuttles two lipid second messengers, i.e., phosphatidylinositol 4,5-bisphosphate and phosphatidylinositol 3,4,5-trisphosphate, and increases their levels in the plasma membrane. Notably, human cancers have markedly upregulated TIPE3 expression. Knocking out TIPE3 diminishes tumorigenesis, whereas enforced TIPE3 expression enhances it in vivo. Thus, the function and metabolism of phosphoinositide second messengers are controlled by a specific transfer protein during tumorigenesis.
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Paxillin suppresses the proliferation of HPS rat serum treated PASMCs by up-regulating the expression of cytoskeletal proteins.
Mol Biosyst
PUBLISHED: 01-23-2014
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Hepatopulmonary syndrome (HPS) is a triad of advanced liver disease, intrapulmonary vasodilatation (IPVD), and arterial hypoxemia. The arterial hypoxemia induces pulmonary vascular remodelling (PVR). In recent studies, the role of the proliferation of pulmonary artery smooth muscle cells (PASMCs) in PVR associated with HPS has been established; the changes in cytoskeletal proteins play an essential role in the proliferation of PASMCs. Little is known about the relevance of cytoskeletal protein expression or the molecular mechanisms of PVR associated with HPS. In addition, it has been identified that paxillin could influence the cytoskeletal protein expression by some important signaling pathways in many diseases, including lung cancer and liver cancer. In this study, we found that HPS rat serum from a common bile duct ligation (CBDL) rat model decreased the expression of cytoskeletal proteins (?-actin, ?-tubulin, and destrin) and enhanced the expression levels of paxillin mRNA and protein in PASMCs. After silencing paxillin with siRNA, we found that the down-regulation of cytoskeletal protein expression, induced by the HPS rat serum, was reversed. Additionally, we reported that HPS rat serum improved the proliferation of PASMCs and down-regulation of paxillin could significantly inhibit this variation. These findings suggest that the up-regulation of cytoskeletal protein expression, induced by the paxillin, may cause the dysregulation of PASMC proliferation as well as play a fundamental role in PVR associated with HPS. In conclusion, down-regulation of paxillin by siRNA results in the inhibition of the dysregulation of cytoskeletal proteins and proliferation of PASMCs, suggesting a potential therapeutic effect on PVR associated with HPS.
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Fluorescent blood glucose monitor by hemin-functionalized graphene quantum dots based sensing system.
Anal. Chim. Acta
PUBLISHED: 01-21-2014
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In the present work, a highly sensitive and specific fluorescent biosensor for blood glucose monitoring is developed based on hemin-functionalized graphene quantum dots (GQDs) and glucose oxidase (GOx) system. The GQDs which are simply prepared by pyrolyzing citric acid exhibit strong fluorescence and good water-solubility. Due to the noncovalent assembly between hemin and GQDs, the addition of hemin can make hydrogen peroxide (H2O2) to destroy the passivated surface of GQDs, leading to significant fluorescence quenching of GQDs. Based on this effect, a novel fluorescent platform is proposed for the sensing of glucose. Under the optimized conditions, the linear range of glucose is from 9 to 300?M, and the limit of detection is 0.1?M. As unique properties of GQDs, the proposed biosensor is green, simple, cost-efficient, and it is successfully applied to the determination of glucose in human serum. In addition, the proposed method provides a new pathway to further design the biosensors based on the assembly of GQDs with hemin for detection of biomolecules.
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Human RAD6 Promotes G1-S Transition and Cell Proliferation through Upregulation of Cyclin D1 Expression.
PLoS ONE
PUBLISHED: 01-01-2014
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Protein ubiquitinylation regulates protein stability and activity. RAD6, an E2 ubiquitin-conjugating enzyme, which that has been substantially biochemically characterized, functions in a number of biologically relevant pathways, including cell cycle progression. In this study, we show that RAD6 promotes the G1-S transition and cell proliferation by regulating the expression of cyclin D1 (CCND1) in human cells. Furthermore, our data indicate that RAD6 influences the transcription of CCND1 by increasing monoubiquitinylation of histone H2B and trimethylation of H3K4 in the CCND1 promoter region. Our study presents, for the first time, an evidence for the function of RAD6 in cell cycle progression and cell proliferation in human cells, raising the possibility that RAD6 could be a new target for molecular diagnosis and prognosis in cancer therapeutics.
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Development of aminoglycoside and ?-lactamase resistance among intestinal microbiota of swine treated with lincomycin, chlortetracycline, and amoxicillin.
Front Microbiol
PUBLISHED: 01-01-2014
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Lincomycin, chlortetracycline, and amoxicillin are commonly used antimicrobials for growth promotion and infectious disease prophylaxis in swine production. In this study, we investigated the shifts and resistance development among intestinal microbiota in pregnant sows before and after lincomycin, chlortetracycline, and amoxicillin treatment by using phylogenetic analysis, bacterial enumeration, and PCR. After the antimicrobial treatment, shifts in microbial community, an increased proportion of resistant bacteria, and genes related to antimicrobial resistance as compared to the day before antimicrobial administration (day 0) were observed. Importantly, a positive correlation between antimicrobial resistance gene expression in different categories, especially those encoding aminoglycoside and ?-lactamase and antimicrobial resistance, was observed. These findings demonstrate an important role of antimicrobial usage in animals in the development of antimicrobial resistance, and support the notion that prudent use of antimicrobials in swine is needed to reduce the risk of the emergence of multi-drug resistant zoonotic pathogens.
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Illumina Amplicon Sequencing of 16S rRNA Tag Reveals Bacterial Community Development in the Rhizosphere of Apple Nurseries at a Replant Disease Site and a New Planting Site.
PLoS ONE
PUBLISHED: 01-01-2014
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We used a next-generation, Illumina-based sequencing approach to characterize the bacterial community development of apple rhizosphere soil in a replant site (RePlant) and a new planting site (NewPlant) in Beijing. Dwarfing apple nurseries of 'Fuji'/SH6/Pingyitiancha trees were planted in the spring of 2013. Before planting, soil from the apple rhizosphere of the replant site (ReSoil) and from the new planting site (NewSoil) was sampled for analysis on the Illumina MiSeq platform. In late September, the rhizosphere soil from both sites was resampled (RePlant and NewPlant). More than 16,000 valid reads were obtained for each replicate, and the community was composed of five dominant groups (Proteobacteria, Acidobacteria, Bacteroidetes, Gemmatimonadetes and Actinobacteria). The bacterial diversity decreased after apple planting. Principal component analyses revealed that the rhizosphere samples were significantly different among treatments. Apple nursery planting showed a large impact on the soil bacterial community, and the community development was significantly different between the replanted and newly planted soils. Verrucomicrobia were less abundant in RePlant soil, while Pseudomonas and Lysobacter were increased in RePlant compared with ReSoil and NewPlant. Both RePlant and ReSoil showed relatively higher invertase and cellulase activities than NewPlant and NewSoil, but only NewPlant soil showed higher urease activity, and this soil also had the higher plant growth. Our experimental results suggest that planting apple nurseries has a significant impact on soil bacterial community development at both replant and new planting sites, and planting on new site resulted in significantly higher soil urease activity and a different bacterial community composition.
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Effects of grazing regimes on plant traits and soil nutrients in an alpine steppe, Northern Tibetan Plateau.
PLoS ONE
PUBLISHED: 01-01-2014
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Understanding the impact of grazing intensity on grassland production and soil fertility is of fundamental importance for grassland conservation and management. We thus compared three types of alpine steppe management by studying vegetation traits and soil properties in response to three levels of grazing pressure: permanent grazing (M1), seasonal grazing (M2), and grazing exclusion (M3) in the alpine steppe in Xainza County, Tibetan Plateau. The results showed that community biomass allocation did not support the isometric hypothesis under different grassland management types. Plants in M1 had less aboveground biomass but more belowground biomass in the top soil layer than those in M2 and M3, which was largely due to that root/shoot ratios of dominant plants in M1 were far greater than those in M2 and M3. The interramet distance and the tiller size of the dominant clonal plants were greater in M3 than in M1 and M2, while the resprouting from rhizome buds did not differ significantly among the three greezing regimes. Both soil bulk density and soil available nitrogen in M3 were greater than in M1 at the 15-30 cm soil depth (P?=?0.05). Soil organic carbon and soil total nitrogen were greater in M3 than in M1 and M2 (P?=?0.05). We conclude that the isometric hypothesis is not supported in this study and fencing is a helpful grassland management in terms of plant growth and soil nutrient retention in alpine steppe. The extreme cold, scarce precipitation and short growing period may be the causation of the unique plant and soil responses to different management regimes.
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TIPE2 negatively regulates inflammation by switching arginine metabolism from nitric oxide synthase to arginase.
PLoS ONE
PUBLISHED: 01-01-2014
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TIPE2, the tumor necrosis factor (TNF)-alpha-induced protein 8-like 2 (TNFAIP8L2), plays an essential role in maintaining immune homeostasis. It is highly expressed in macrophages and negatively regulates inflammation through inhibiting Toll-like receptor signaling. In this paper, we utilized RAW264.7 cells stably transfected with a TIPE2 expression plasmid, as well as TIPE2-deficient macrophages to study the roles of TIPE2 in LPS-induced nitric oxide (NO) and urea production. The results showed that TIPE2-deficiency significantly upregulated the levels of iNOS expression and NO production in LPS-stimulated macrophages, but decreased mRNA levels of arginase I and urea production. However, TIPE2 overexpression in macrophages was capable of downregulating protein levels of LPS-induced iNOS and NO, but generated greater levels of arginase I and urea production. Furthermore, TIPE2-/- mice had higher iNOS protein levels in lung and liver and higher plasma NO concentrations, but lower levels of liver arginase I compared to LPS-treated WT controls. Interestingly, significant increases in I?B degradation and phosphorylation of JNK, p38, and I?B were observed in TIPE2-deficient macrophages following LPS challenge. These results strongly suggest that TIPE2 plays an important role in shifting L-arginase metabolism from production of NO to urea, during host inflammatory response.
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Synergistic and antagonistic effects of salinity and pH on germination in switchgrass (Panicum virgatum L.).
PLoS ONE
PUBLISHED: 01-01-2014
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The effects of salt-alkaline mixed stress on switchgrass were investigated by evaluating seed germination and the proline, malondialdehyde (MDA) and soluble sugar contents in three switchgrass (Panicum virgatum L.) cultivars in order to identify which can be successfully produced on marginal lands affected by salt-alkaline mixed stress. The experimental conditions consisted of four levels of salinity (10, 60, 110 and 160 mM) and four pH levels (7.1, 8.3, 9.5 and 10.7). The effects of salt-alkaline mixed stress with equivalent coupling of the salinity and pH level on the switchgrass were explored via model analyses. Switchgrass was capable of germinating and surviving well in all treatments under low-alkaline pH (pH?8.3), regardless of the salinity. However, seed germination and seedling growth were sharply reduced at higher pH values in conjunction with salinity. The salinity and pH had synergetic effects on the germination percentage, germination index, plumular length and the soluble sugar and proline contents in switchgrass. However, these two factors exhibited antagonistic effects on the radicular length of switchgrass. The combined effects of salinity and pH and the interactions between them should be considered when evaluating the strength of salt-alkaline mixed stress.
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Animated Depth Images for Interactive Remote Visualization of Time-Varying Datasets.
IEEE Trans Vis Comput Graph
PUBLISHED: 11-27-2013
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Remote-visualization has become both a necessity, as dataset sizes have grown faster than computer network performance, and an opportunity, as mobile computing platforms have become ubiquitous. However, the conventional remote-visualization approach of sending new images from the server to the client for every view-parameter change suffers from reduced interactivity. One problem is high latency, as the network has to be traversed twice for each interaction of client with server. A second problem is reduced image quality due to aggressive compression or reduced resolution. We address these problems by constructing and transmitting enhanced images that are sufficient for quality output frame reconstruction at the client for a range of view-parameter values. The client reconstructs thousands of frames locally, without any additional data from the server, which avoids latency and aggressive compression. We introduce animated depth images, which not only store a color and depth sample at every pixel, but also store the trajectory of the samples for a given time interval. Sample trajectories are stored compactly by partitioning the image into semi-rigid sample clusters and by storing one sequence of rigid body transformations per cluster. Animated depth images leverage sample trajectory coherence to achieve a good compression of animation data, with a small and user-controllable approximation error.
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Accumulation of Fascin+ cells during experimental autoimmune neuritis.
Diagn Pathol
PUBLISHED: 10-24-2013
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Experimental autoimmune neuritis (EAN) is a well-known animal model of human demyelinating polyneuropathies and is characterized by inflammation and demyelination in the peripheral nervous system. Fascin is an evolutionarily highly conserved cytoskeletal protein of 55 kDa containing two actin binding domains that cross-link filamentous actin to hexagonal bundles.
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Effect of oxidative stress on sympathetic and renal vascular responses to ischemic exercise.
Physiol Rep
PUBLISHED: 10-08-2013
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Reactive oxygen species (ROS), produced acutely during skeletal muscle contraction, are known to stimulate group IV muscle afferents and accentuate the exercise pressor reflex (EPR) in rodents. The effect of ROS on the EPR in humans is unknown. We conducted a series of studies using ischemic fatiguing rhythmic handgrip to acutely increase ROS within skeletal muscle, ascorbic acid infusion to scavenge free radicals, and hyperoxia inhalation to further increase ROS production. We hypothesized that ascorbic acid would attenuate the EPR and that hyperoxia would accentuate the EPR. Ten young healthy subjects participated in two or three experimental trials on separate days. Beat-by-beat measurements of heart rate (HR), mean arterial pressure (MAP), muscle sympathetic nerve activity (MSNA), and renal vascular resistance index (RVRI) were measured and compared between treatments (saline and ascorbic acid; room air and hyperoxia). At fatigue, the reflex increases in MAP (31 ± 3 versus 29 ± 2 mmHg), HR (19 ± 3 versus 20 ± 3 bpm), MSNA burst rate (21 ± 4 versus 23 ± 4 burst/min), and RVRI (39 ± 12 versus 44 ± 13%) were not different between saline and ascorbic acid. Relative to room air, hyperoxia did not augment the reflex increases in MAP, HR, MSNA, or RVRI in response to exercise. Muscle metaboreflex activation and time/volume control experiments similarly showed no treatment effects. While contrary to our initial hypotheses, these findings suggest that ROS do not play a significant role in the normal reflex adjustments to ischemic exercise in young healthy humans.
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Histochemical examination of cathepsin K, MMP1 and MMP2 in compressed periodontal ligament during orthodontic tooth movement in periostin deficient mice.
J. Mol. Histol.
PUBLISHED: 08-15-2013
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The purpose of this study was to investigate immunolocalization of collagenolytic enzymes including cathepsin K, matrix metalloproteinase (MMP) 1 and 2 in the compressed periodontal ligament (PDL) during orthodontic tooth movement using a periostin deficient (Pn-/-) mouse model. Twelve-week-old male mice homozygous for the disrupted periostin gene and their wild type (WT) littermates were used in these experiments. The tooth movement was performed according to Waldos method, in which elastic bands of 0.5 mm thickness were inserted between the first and second upper molars of mice under anesthesia. At 1 and 3 days after orthodontic force application, mice were fixed with transcardial perfusion of 4 % paraformaldehyde in 0.1 M phosphate buffer (pH 7.4), and the first molars and peripheral alveolar bones were extracted for histochemical analyses. Compared with WT mice, immunolocalization of cathepsin K, MMP1 and MMP2 was significantly decreased at 1 and 3 days after orthodontic tooth movement in the compressed PDL of Pn-/- mice, although MMP1-reactivity and MMP2-reactivity decreased at different amounts. Very little cathepsin K-immunoreactivity was observed in the assessed regions of Pn-/- mice, both before and after orthodontic force application. Furthermore, Pn-/- mice showed a much wider residual PDL than WT mice. Taken together, we concluded that periostin plays an essential role in the function of collagenolytic enzymes like cathepsin K, MMP1 and MMP2 in the compressed PDL after orthodontic force application.
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Distension of central great vein decreases sympathetic outflow in humans.
Am. J. Physiol. Heart Circ. Physiol.
PUBLISHED: 05-31-2013
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Classic canine studies suggest that central great vein distension evokes an autonomic reflex tachycardia (Bainbridge reflex). It is unclear whether central venous distension in humans is a necessary and sufficient stimulus to evoke a reflex increase in heart rate (HR), blood pressure (BP), and muscle sympathetic nerve activity (MSNA). Prior work from our laboratory suggests that limb venous distension evokes a reflex increase in BP and MSNA in humans. We hypothesized that in humans, compared with the limb venous distension, inferior vena cava (IVC) distension would evoke a less prominent increase in HR and MSNA. IVC distension (monitored with ultrasonography) was induced by two methods: 1) head-down tilt (HDT, N = 13); and 2) lower-body positive pressure (LBPP, N = 10). Two minutes of HDT induced IVC distension (?2.6 ± 0.2 mm, P < 0.001, ~27% in cross-sectional area), slightly increased mean BP (?2.3 ± 0.7 mmHg, P = 0.005), decreased MSNA (?5.2 ± 0.8 bursts/min, P < 0.001, N = 10), and did not alter HR (P = 0.37). LBPP induced similar IVC distension, increased BP (?2.0 ± 0.7 mmHg, P < 0.01), and did not alter HR (P = 0.34). Thus central venous distension leads to a rapid increase in BP and a subsequent fall in MSNA. Central venous distension does not evoke either bradycardia or tachycardia in humans. The absence of a baroreflex-mediated bradycardia suggests that the Bainbridge reflex is engaged. Clearly, this reflex differs from the powerful sympathoexcitation peripheral venous distension reflex described in humans.
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[Mechanisms of EGF regulation of COX-2 through the STAT5 signaling pathway in human lung adenocarcinoma A549 cells].
Zhongguo Fei Ai Za Zhi
PUBLISHED: 04-23-2013
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It has been proved that cyclooxygenase-2 (COX-2) is a key factor in lung cancer oncogenesis. COX-2 can be induced by a number of cytokines and growth factors and can be regulated by the JAK/STAT signaling pathway. Inhibiting the expression of COX-2 can prevent the development of lung cancer. The aim fo this study is to investigate whether the epidermal growth factor (EGF) can stimulate the signal transducers and activators of transcription 5 (STAT5) as well as to discover the effects of the STAT5 signaling pathway on the COX-2 in human lung adenocarcinoma A549 cells.
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Tactile stimulation of the oropharynx elicits sympathoexcitation in conscious humans.
J. Appl. Physiol.
PUBLISHED: 04-18-2013
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Tactile stimulation of the oropharynx (TSO) elicits the gag reflex and increases heart rate (HR) and mean arterial pressure (MAP) in anesthetized patients. However, the interaction between upper-airway defense reflexes and the sympathetic nervous system has not been investigated in conscious humans. In Experiment 1, beat-by-beat measurements of HR, MAP, muscle sympathetic nerve activity (MSNA), and renal vascular resistance (RVR) were measured during TSO and tactile stimulation of the hard palate (Sham) in the supine posture. In Experiment 2, TSO was performed before (pre) and after (post) inhalation of 4% lidocaine via nebulizer. Rate pressure product (RPP) was determined. Compared with Sham, TSO elicited the gag reflex and increased RPP [absolute change (?)36 ± 6 vs. 17 ± 5%], MSNA (?122 ± 39 vs. 19 ± 19%), and RVR (?55 ± 11 vs. 4 ± 4%). This effect occurred within one to two cardiac cycles of TSO. The ?MAP (12 ± 3 vs. 6 ± 1 mmHg) and the ?HR (10 ± 3 vs. 3 ± 3 beats/min) were also greater following TSO compared with Sham. Lidocaine inhalation blocked the gag reflex and attenuated increases in MAP (?pre: 16 ± 2; ?post: 5 ± 2 mmHg) and HR (?pre: 12 ± 3; ?post: 2 ± 2 beats/min) in response to TSO. When mechanically stimulated, afferents in the oropharynx not only serve to protect the airway but also cause reflex increases in MSNA, RVR, MAP, and HR. An augmented sympathoexcitatory response during intubation and laryngoscopy may contribute to perioperative cardiovascular morbidity and mortality.
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[Impacts of climate warming on nine element contents in Mongolian drug Agi using ICP-AES].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 04-17-2013
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Global warming has become a fact of life, and the night temperature increase higher than during the day. In the present research, to explore the effects of climate warming on element contents of plants, ICP-AES was used for the direct determination of nine kinds of element contents of reproductive branches and vegetative branches of the Mongolian drug Agi, which grew in the day, night and diurnal warming field. The results of the study show that the responses of reproductive branches and vegetative branches to day, night and diurnal warming were not significant different, but the negative response was greater than the positive response. The effects of day warming on the element contents were not significant, but night warming lower the contents of Al, Fe and Mn significantly. There was interaction between day warming and night warming.
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Vascular transcriptional alterations produced by juvenile obesity in Ossabaw swine.
Physiol. Genomics
PUBLISHED: 04-16-2013
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We adopted a transcriptome-wide microarray analysis approach to determine the extent to which vascular gene expression is altered as a result of juvenile obesity and identify obesity-responsive mRNAs. We examined transcriptional profiles in the left anterior descending coronary artery (LAD), perivascular fat adjacent to the LAD, and descending thoracic aorta between obese (n = 5) and lean (n = 6) juvenile Ossabaw pigs (age = 22 wk). Obesity was experimentally induced by feeding the animals a high-fat/high-fructose corn syrup/high-cholesterol diet for 16 wk. We found that expression of 189 vascular cell genes in the LAD and expression of 165 genes in the thoracic aorta were altered with juvenile obesity (false discovery rate ? 10%) with an overlap of only 28 genes between both arteries. Notably, a number of genes found to be markedly upregulated in the LAD of obese pigs are implicated in atherosclerosis, including ACP5, LYZ, CXCL14, APOE, PLA2G7, LGALS3, SPP1, ITGB2, CYBB, and P2RY12. Furthermore, pathway analysis revealed the induction of proinflammatory and pro-oxidant pathways with obesity primarily in the LAD. Gene expression in the LAD perivascular fat was minimally altered with juvenile obesity. Together, we provide new evidence that obesity produces artery-specific changes in pretranslational regulation with a clear upregulation of proatherogenic genes in the LAD. Our data may offer potential viable drug targets and mechanistic insights regarding the molecular precursors involved in the origins of overnutrition and obesity-associated vascular disease. In particular, our results suggest that the oxidized LDL/LOX-1/NF-?B signaling axis may be involved in the early initiation of a juvenile obesity-induced proatherogenic coronary artery phenotype.
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Fast-track surgery improves postoperative clinical recovery and reduces postoperative insulin resistance after esophagectomy for esophageal cancer.
Support Care Cancer
PUBLISHED: 03-11-2013
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This study aims to investigate the influence of fast-track surgery (FTS) on insulin resistance indicators in a prospective randomized, controlled clinical trial in esophageal cancer patients.
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Chimeric antigen receptor containing ICOS signaling domain mediates specific and efficient antitumor effect of T cells against EGFRvIII expressing glioma.
J Hematol Oncol
PUBLISHED: 02-19-2013
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Adoptive transfer of chimeric antigen receptor (CAR)-modified T cells appears to be a promising immunotherapeutic strategy. CAR combines the specificity of antibody and cytotoxicity of cytotoxic T lymphocytes, enhancing T cells ability to specifically target antigens and to effectively kill cancer cells. Recent efforts have been made to integrate the costimulatory signals in the CAR to improve the antitumor efficacy. Epidermal growth factor receptor variant III (EGFRvIII) is an attractive therapeutic target as it frequently expresses in glioma and many other types of cancers. Our current study aimed to investigate the specific and efficient antitumor effect of T cells modified with CAR containing inducible costimulator (ICOS) signaling domain.
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Inhibition of HCN channels within the periaqueductal gray attenuates neuropathic pain in rats.
Behav. Neurosci.
PUBLISHED: 02-11-2013
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Peripheral and spinal hyperpolarization-activated cyclic nucleotide-gated cation (HCN) channels play important roles in neuropathic pain by regulating neuronal excitability. However, the participation of HCN channels in the ventral-lateral periaqueductal gray (vlPAG) during neuropathic pain states has not been clarified. To investigate the role of vlPAG HCN channels in neuropathic pain, the authors developed a chronic constriction injury (CCI) model. By using western blot analysis, they detected the upregulation of HCN1 and HCN2 channel expression at vlPAG 14 days post-CCI surgery. Subsequently, the function of these upregulated channels was verified by the intravlPAG infusion of ZD7288, a specific HCN blocker, which significantly relieved mechanical allodynia and thermal hyperalgesia in CCI animals. These results suggest that the upregulation of vlPAG HCN channels plays an important role in pain maintenance and might be a target for attenuating pain.
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Chronic heart failure does not attenuate the total activity of sympathetic outflow to skin during whole-body heating.
Circ Heart Fail
PUBLISHED: 02-08-2013
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Previous studies show that the rise in skin blood flow and cutaneous vascular conductance during heat stress is substantially attenuated in chronic heart failure (CHF) patients. The mechanisms responsible for this finding are not clear. In particular, little is known regarding the responses of skin sympathetic nerve activity (SSNA) that control the skin blood flow during heat stress in CHF patients. We examined the effects of a modest heat stress to test the hypothesis that SSNA responses could be attenuated in CHF.
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Antimicrobial and antioxidant activities of Cichorium intybus root extract using orthogonal matrix design.
J. Food Sci.
PUBLISHED: 02-08-2013
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Solvent, impregnation time, sonication repetitions, and ultrasonic power were important factors in the process of ultrasound-assisted extraction from chicory (Cichorium intybus) root, while there were no studies about optimizing these 4 factors for extract yield, total phenolic content (TPC), antioxidant, antibacterial, and antifungal activity of the extracts using orthogonal matrix design. The present research demonstrated that the solvent composition played a significant role in the improving extract yield, TPC, antioxidant, and antibacterial activities. The other 3 factors had inequable effect on different purposes, ultrasonic power could improve TPC and antioxidant activity, but long time of extraction lowered antioxidant activity. The TPC increased from 22.34 to 27.87 mg GAE (gallic acid equivalents)/100 g (dry extracts) with increasing solvent polarity. The half inhibition concentration (IC(50,) ?g/mL) of the radical scavenging activity of the chicory extracts ranged from 281.00 to 983.33 ?g/mL. The content of caffeoylquinic acids of root extract, which was extracted by the optimal combination was 0.104%. Several extracts displayed antibacterial activities against Escherichia coli, Staphylococcus aureus, Bacillus thuringiensis, Bacillus subtilis, and Salmonella typhi, while Penicillium sp. and Aspergillus sp. resisted against all the extracts. Combination of 70% ethanol v/v, 24-h impregnation time, 3 sonication rounds, and 300-W ultrasonic input power was found to be the optimal combination for the chicory extract yield, TPC, antioxidant activity, and antibacterial activity.
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Effect of calcium on the kinetics of free fatty acid release during in vitro lipid digestion in model emulsions.
Food Chem
PUBLISHED: 02-05-2013
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The effects of different calcium salts on in vitro lipid digestion were examined by determining the free fatty acids released from various oil-in-water emulsions. The kinetics of the total and individual free fatty acids released by lipolysis were monitored by the pH-stat method and gas chromatography, respectively. The rate and the extent of free fatty acid release increased with an increase in the added calcium concentration, but the increase was dependent on the emulsifying agent. The effect of calcium was diminished when the emulsion contained phosphate. Soluble calcium salts, such as calcium gluconate, calcium acetate and CaCl2, had greater effects on the rate and extent of free fatty acid release than did insoluble salts, such as CaO and CaSO4, suggesting that the ionic state of calcium plays a critical role in lipid digestion in emulsions. The addition of calcium did not alter the profiles of the individual free fatty acids released. This study provides useful information for food formulation with respect to lipid digestion.
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Compact high-quality CdSe-CdS core-shell nanocrystals with narrow emission linewidths and suppressed blinking.
Nat Mater
PUBLISHED: 02-03-2013
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High particle uniformity, high photoluminescence quantum yields, narrow and symmetric emission spectral lineshapes and minimal single-dot emission intermittency (known as blinking) have been recognized as universal requirements for the successful use of colloidal quantum dots in nearly all optical applications. However, synthesizing samples that simultaneously meet all these four criteria has proven challenging. Here, we report the synthesis of such high-quality CdSe-CdS core-shell quantum dots in an optimized process that maintains a slow growth rate of the shell through the use of octanethiol and cadmium oleate as precursors. In contrast with previous observations, single-dot blinking is significantly suppressed with only a relatively thin shell. Furthermore, we demonstrate the elimination of the ensemble luminescence photodarkening that is an intrinsic consequence of quantum dot blinking statistical ageing. Furthermore, the small size and high photoluminescence quantum yields of these novel quantum dots render them superior in vivo imaging agents compared with conventional quantum dots. We anticipate these quantum dots will also result in significant improvement in the performance of quantum dots in other applications such as solid-state lighting and illumination.
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Direct observation of rapid discrete spectral dynamics in single colloidal CdSe-CdS core-shell quantum dots.
Phys. Rev. Lett.
PUBLISHED: 01-25-2013
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We measure the anomalous spectral diffusion of single colloidal quantum dots over eight temporal decades simultaneously by combining single-molecule spectroscopy and photon-correlation Fourier spectroscopy. Our technique distinguishes between discrete and continuous dynamics and directly reveals that the quasicontinuous spectral diffusion observed using conventional spectroscopy is composed of rapid, discrete spectral jumps. Despite their multiple time scales, these dynamics can be captured by a single mechanism whose parameters vary widely between dots and over time in individual dots.
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A primary pulmonary glomus tumor complicated with hyperpyrexia and anemia.
Ann. Thorac. Surg.
PUBLISHED: 01-23-2013
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Pulmonary glomus tumors are extremely rare, with only 19 cases having been reported worldwide. The glomus body is considered to be related to the regulation of body temperature, but the reported cases were not associated with hyperpyrexia. Here, we describe a 28-year-old man with hyperpyrexia and anemia complicated with a coin lesion of the right lung. After resection of the upper lobe of the right lung by video-assisted thoracoscopic surgery, all of the patients symptoms disappeared. The pathologic analysis reported a rare pulmonary glomus tumor. The disease had not recurred by 1 year after operation.
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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.

Video X seems to be unrelated to Abstract Y...

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.