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Find video protocols related to scientific articles indexed in Pubmed.
Choline phosphate functionalized surface: protein-resistant but cell-adhesive zwitterionic surface potential for tissue engineering.
Chem. Commun. (Camb.)
PUBLISHED: 11-20-2014
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A choline phosphate (CP) modified surface is designed to resist protein adsorption due to its zwitterionic properties and simultaneously promote cell adhesion though its universal interaction with phosphate choline (PC) headgroups of the cell membrane. This work provides a new approach to obtain a cell-adhesive surface with a non-biofouling 'background', which has a potential for tissue engineering.
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Formation of 100-nm periodic structures on a titanium surface by exploiting the oxidation and third harmonic generation induced by femtosecond laser pulses.
Opt Express
PUBLISHED: 11-18-2014
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Periodic surface structures with periods as small as about one-tenth of the irradiating femtosecond (fs) laser light wavelength were created on the surface of a titanium (Ti) foil by exploiting laser-induced oxidation and third harmonic generation (THG). They were achieved by using 100-fs laser pulses with a repetition rate of 1 kHz and a wavelength ranging from 1.4 to 2.2 ?m. It was revealed that an extremely thin TixOy layer was formed on the surface of the Ti foil after irradiating fs laser light with a fluence smaller than the ablation threshold of Ti, leading to a significant enhancement in THG which may exceed the ablation threshold of TixOy. As compared with Ti, the maximum efficacy factor for TixOy appears at a larger normalized wavevector in the direction perpendicular to the polarization of the fs laser light. As a result, the THG-dominated laser ablation of TixOy induces 100-nm periodic structures parallel to the polarization of the fs laser light. The depth of the periodic structures was found to be ~10 nm by atomic force microscopy and the formation of the thin TixOy layer was verified by energy dispersive X-ray spectroscopy.
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Robust boundary detection and tracking of left ventricles on ultrasound images using active shape model and ant colony optimization.
Biomed Mater Eng
PUBLISHED: 09-18-2014
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Information regarding the motion, strain and synchronization are important for cardiac diagnosis and therapy. Extraction of such information from ultrasound images remains an open problem till today. In this paper, a novel method is proposed to extract the boundaries of left ventricles and track these boundaries in ultrasound image sequences. The initial detection of boundaries was performed by an active shape model scheme. Subsequent refinement of the boundaries was done by using local variance information of the images. The main objective of this paper is the formulation of a new boundary tracking algorithm using ant colony optimization technique. The experiments conducted on the simulated image sequences and the real cardiac ultrasound image sequences shows a positive and promising result.
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Optimization of Process Parameters of Extraction of Amentoflavone, Quercetin and Ginkgetin from Taxus chinensis Using Supercritical CO2 Plus Co-Solvent.
Molecules
PUBLISHED: 09-10-2014
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The effects of extraction time, temperature, pressure and different concentration of ethanol and their interactions on the yields of amentoflavone, quercetin and ginkgetin extracted from Taxus chinensis by supercritical CO2 were investigated by using a central composite design (CCD). An CCD experimental design with four factors and five levels was used to optimize the extraction parameters. Ultra performance liquid chromatography (UPLC) was used to analyze the content of the tree components in the extracts. Experimental results show that the main effects of factors and their interactions are significant on the yields (p < 0.05). The optimal extraction conditions were established for the three compounds: yield of 4.47 mg/g for amentoflavone at 48 °C, 25 MPa, 2.02 h and 78.5% ethanol, 3.73 mg/g for quercetin at 46 °C, 24 MPa, 2.3 h, 82% ethanol and 3.47 mg/g for ginkgetin at 48 °C, 20 MPa, 2.38 h, 82% ethanol, respectively.
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A cluster-randomized controlled trial to evaluate the effects of a simplified cardiovascular management program in Tibet, China and Haryana, India: study design and rationale.
BMC Public Health
PUBLISHED: 08-28-2014
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In resource-poor areas of China and India, the cardiovascular disease burden is high, but availability of and access to quality healthcare is limited. Establishing a management scheme that utilizes the local infrastructure and builds healthcare capacity is essential for cardiovascular disease prevention and management. The study aims to develop, implement, and evaluate the feasibility and effectiveness of a simplified, evidence-based cardiovascular management program delivered by community healthcare workers in resource-constrained areas in Tibet, China and Haryana, India.
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Terahertz spectroscopic investigation of human gastric normal and tumor tissues.
Phys Med Biol
PUBLISHED: 08-28-2014
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Human dehydrated normal and cancerous gastric tissues were measured using transmission time-domain terahertz spectroscopy. Based on the obtained terahertz absorption spectra, the contrasts between the two kinds of tissue were investigated and techniques for automatic identification of cancerous tissue were studied. Distinctive differences were demonstrated in both the shape and amplitude of the absorption spectra between normal and tumor tissue. Additionally, some spectral features in the range of 0.2~0.5?THz and 1~1.5?THz were revealed for all cancerous gastric tissues. To systematically achieve the identification of gastric cancer, principal component analysis combined with t-test was used to extract valuable information indicating the best distinction between the two types. Two clustering approaches, K-means and support vector machine (SVM), were then performed to classify the processed terahertz data into normal and cancerous groups. SVM presented a satisfactory result with less false classification cases. The results of this study implicate the potential of the terahertz technique to detect gastric cancer. The applied data analysis methodology provides a suggestion for automatic discrimination of terahertz spectra in other applications.
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Phytotoxicity of 4,8-dihydroxy-1-tetralone isolated from Carya cathayensis Sarg. to various plant species.
Molecules
PUBLISHED: 08-19-2014
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The aqueous extract from Carya cathayensis Sarg. exocarp was centrifuged, filtered, and separated into 11 elution fractions by X-5 macroporous resin chromatography. A phenolic compound, 4,8-dihydroxy-1-tetralone (4,8-DHT) was isolated from the fractions with the strongest phytotoxicity by bioassy-guided fractionation, and investigated for phytotoxicity on lettuce (Latuca sativa L.), radish (Raphanus sativus L.), cucumber (Cucumis sativus L.), onion (Allium cepa L.) and wheat (Triticum aestivum L.). The testing results showed that the treatment with 0.6 mM 4,8-DHT could significantly depress the germination vigor of lettuce and wheat, reduce the germination rate of lettuce and cucumber, and also inhibit radicle length, plumule length, and fresh weight of seedlings of lettuce and onion, but could significantly promote plumule length and fresh weight of seedlings of cucumber (p < 0.05). For the tested five plants, the 4,8-DHT was the most active to the seed germination and seedling growth of lettuce, indicating that the phytotoxicity of 4,8-DHT had the selectivity of dosage, action target (plant type) and content (seed germination or seedling growth).
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Predictive value of decoy receptor 3 in postoperative nosocomial bacterial meningitis.
Int J Mol Sci
PUBLISHED: 08-13-2014
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Nosocomial bacterial meningitis requires timely treatment, but what is difficult is the prompt and accurate diagnosis of this disease. The aim of this study was to assess the potential role of decoy receptor 3 (DcR3) levels in the differentiation of bacterial meningitis from non-bacterial meningitis. A total of 123 patients were recruited in this study, among them 80 patients being with bacterial meningitis and 43 patients with non-bacterial meningitis. Bacterial meningitis was confirmed by bacterial culture of cerebrospinal fluid (CSF) culture and enzyme-linked immunosorbent assay (ELISA) was used to detect the level of DcR3 in CSF. CSF levels of DcR3 were statistically significant between patients with bacterial meningitis and those with non-bacterial meningitis (p < 0.001). A total of 48.75% of patients with bacterial meningitis received antibiotic >24 h before CSF sampling, which was much higher than that of non-bacterial meningitis. CSF leucocyte count yielded the highest diagnostic value, with an area under the receiver operating characteristic curve (ROC) of 0.928, followed by DcR3. At a critical value of 0.201 ng/mL for DcR3, the sensitivity and specificity were 78.75% and 81.40% respectively. DcR3 in CSF may be a valuable predictor for differentiating patients with bacterial meningitis from those with non-bacterial meningitis. Further studies are needed for the validation of this study.
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[Inducing-apoptosis effect of brucine on human monocytic leukemia cell line THP-1 and its mechanism].
Zhongguo Shi Yan Xue Ye Xue Za Zhi
PUBLISHED: 07-04-2014
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This study was aimed to investigate the inducing-apoptosis effect of brucine on human monocytic leukemia cell line THP-1 cells and its possible mechanism. The inhibition effect of brucine on growth of THP-1 cells was measured by CCK-8 method. Morphological changes of THP-1 cells treated with brucine was detected by acridine orange/ethidium bromide (AO/EB)double staining. Annexin-V/PI double labeling method was used to assay the apoptosis rate of THP-1 cells. The effect of brucine on THP-1 cell cycle distribution was detected by PI single staining. RT-PCR was used to detect the expression of BCL-2 and BAX. The results showed that the brucine could inhibit the THP-1 cell growth in concentration and time-dependent manners at the range of 50 to 400 µg/ml. The cells stained with AO/EB revealed that the brucine induced the nuclear chromatin condensation. After the THP-1 cells were treated with brucine of 400µg/ml for 48 hours, most nucleis were stained as orange-red, and condensed, displaying the late apoptotic cell morphology. Annexin-V/PI detection showed that brucine could induce apoptosis of THP-1 cells in a concentration-dependent manner. Compared with the control group, more cells in brucine-treated group were arrested at G0/G1 phase in a concentration-dependent manner. RT-PCR detection revealed that the expression of BCL-2 was down-regulated strikingly and BAX was up-regulated. It is concluded that brucine can efficiently inhibit cell growth and block THP-1 cells in G0/G1 phase. The mechanism of THP-1 cell apoptosis induced by brucine may be related to the inhibition of BCL-2 and activation of BAX.
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Hippocampal Wnt3a is Necessary and Sufficient for Contextual Fear Memory Acquisition and Consolidation.
Cereb. Cortex
PUBLISHED: 06-07-2014
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The Wnt signaling pathway plays critical roles in development. However, to date, the role of Wnts in learning and memory in adults is still not well understood. Here, we aimed to investigate the roles and mechanisms of Wnts in hippocampal-dependent contextual fear conditioning (CFC) memory formation in adult mice. CFC training induced the secretion and expression of Wnt3a and the activation of its downstream Wnt/Ca(2+) and Wnt/?-catenin signaling pathways in the dorsal hippocampus (DH). Intrahippocampal infusion of Wnt3a antibody impaired CFC acquisition and consolidation, but not expression. Using the Wnt antagonist sFRP1 or the canonical Wnt inhibitor Dkk1, we found that Wnt/Ca(2+) and Wnt/?-catenin signaling pathways were involved in acquisition and consolidation, respectively. Moreover, we found Wnt3a signaling is not only necessary but also sufficient for CFC memory. Intrahippocampal infusion of exogenous Wnt3a could enhance acquisition and consolidation of CFC. Overexpression of constitutively active ?-catenin in the DH could rescue the deficit in CFC memory consolidation, but not acquisition induced by Wnt3a antibody injection, which suggests ?-catenin signaling pathway acts downstream of Wnt3a to mediate CFC memory consolidation. Our study may help further the understanding of the precise regulation of Wnt3a in differential memory phases depending on divergent signaling pathways.
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[Effects of octreotide on fatty infiltration of the pancreas in high-fat diet induced obesity rats].
Wei Sheng Yan Jiu
PUBLISHED: 05-30-2014
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To investigate effects of octreotide on fatty infiltration of the pancreas in high-fat diet induced obesity rats.
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Syntaxin 8 modulates the post-synthetic trafficking of the TrkA receptor and inflammatory pain transmission.
J. Biol. Chem.
PUBLISHED: 05-28-2014
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Nerve growth factor (NGF) promotes the survival, maintenance, and neurite outgrowth of sensory and sympathetic neurons, and the effects are mediated by TrkA receptor signaling. Thus, the cell surface location of the TrkA receptor is crucial for NGF-mediated functions. However, the regulatory mechanism underlying TrkA cell surface levels remains incompletely understood. In this study, we identified syntaxin 8 (STX8), a Q-SNARE protein, as a novel TrkA-binding protein. Overexpression and knockdown studies showed that STX8 facilitates TrkA transport from the Golgi to the plasma membrane and regulates the surface levels of TrkA but not TrkB receptors. Furthermore, STX8 modulates downstream NGF-induced TrkA signaling and, consequently, the survival of NGF-dependent dorsal root ganglia neurons. Finally, knockdown of STX8 in rat dorsal root ganglia by recombinant adeno-associated virus serotype 6-mediated RNA interference led to analgesic effects on formalin-induced inflammatory pain. These findings demonstrate that STX8 is a modulator of TrkA cell surface levels and biological functions.
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Activator- and repressor-type MYB transcription factors are involved in chilling injury induced flesh lignification in loquat via their interactions with the phenylpropanoid pathway.
J. Exp. Bot.
PUBLISHED: 05-24-2014
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Lignin biosynthesis and its transcriptional regulatory networks have been studied in model plants and woody trees. However, lignification also occurs in some fleshy fruit and has rarely been considered in this way. Loquat ( Eriobotrya japonica ) is one such convenient tissue for exploring the transcription factors involved in regulating fruit flesh lignification. Firmness and lignin content of 'Luoyangqing' loquat were fund to increase during low-temperature storage as a typical symptom of chilling injury, while heat treatment (HT) and low-temperature conditioning (LTC) effectively alleviated them. Two novel EjMYB genes, EjMYB1 and EjMYB2, were isolated and were found to be localized in the nucleus. These genes responded differently to low temperature, with EjMYB1 induced and EjMYB2 inhibited at 0 °C. They also showed different temperature responses under HT and LTC conditions, and may be responsible for different regulation of flesh lignification at the transcriptional level. Transactivation assays indicated that EjMYB1 and EjMYB2 are a transcriptional activator and repressor, respectively. EjMYB1 activated promoters of both Arabidopsis and loquat lignin biosynthesis genes, while EjMYB2 countered the inductive effects of EjMYB1. This finding was also supported by transient overexpression in tobacco. Regulation of lignification by EjMYB1 and EjMYB2 is likely to be achieved via their competitive interaction with AC elements in the promoter region of lignin biosynthesis genes such as Ej4CL1.
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Melatonin promotes the acquisition of neural identity through extracellular-signal-regulated kinases 1/2 activation.
J. Pineal Res.
PUBLISHED: 05-10-2014
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Melatonin, a major pineal secretory product, exerts a range of physiological and neuroprotective effects. However, the functional significance of melatonin in determining neural identity, and the mechanisms by which this may occur, is unknown. In this study, P19 cells were used as a model system and cell behavior was monitored. Our data show that melatonin plays an important role in determining cell fate during neural commitment and promoting the differentiation of pluripotent P19 cells (Oct4(+) Sox2(+) ) into neural stem cells (Oct4(-) Sox2(+) ). This promotion appears to coincide with the activation of the MT1 receptor and phosphorylation of extracellular-signal-regulated kinases 1/2 (ERK1/2). Furthermore, our results show that melatonin regulates neural fate specification of P19 cells through two distinct mechanisms: the promotion of nuclear localization of ERK1/2 and upregulation of Sox2 transcription, and suppression of Smad1-induced expression of mesodermal-specific genes, such as Bra.
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Simultaneous Purification of Limonin, Nomilin and Isoobacunoic Acid from Pomelo Fruit (Citrus grandis) Segment Membrane.
J. Food Sci.
PUBLISHED: 04-23-2014
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A method was established for purification of limonin, nomilin, and isoobacunoic acid simultaneously from segment membranes of pomelo (Citrus Grandis). This method includes 3 steps, removing most impurities by macroporous resin HZ-816, isolating limonin by High Speed Counter Current Chromatography (HSCCC), and isolating nomilin and isoobacunoic acid by semi-preparative HPLC. Naringin was partially purified as a by-product of this process using Sephadex LH-20. All limonoids purified through this method reached 95% purity. The purified limonin, nomilin and isoobacunoic acid were identified according to the retention time of the standard substances using HPLC and characteristic fragment ions of LC-MS/MS.
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Role of postnatal expression of fgfr1 and fgfr2 in testicular germ cells on spermatogenesis and fertility in mice.
J Reprod Infertil
PUBLISHED: 04-19-2014
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Fibroblast growth factor (FGF) signaling is thought to play diverse roles in the male reproductive system. However, its role in testicular cells for spermatogenesis and fertility remains unclear.
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A risk score model for the metastasis of level Ib lymph node based on the clinicopathological features of nasopharyngeal carcinoma in a large sample.
Mol Clin Oncol
PUBLISHED: 04-11-2014
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The aim of the present study was to develop a metastatic risk score model of neck level Ib lymph nodes in primary nasopharyngeal carcinoma (NPC) to guide the level Ib radiotherapy. There were a total of 1,557 patients enrolled in the study, and of these patients, 1,145 were included in the training set. Univariate ?(2) analysis and multivariate logistic regression analyses were used to screen the independent risk factors to construct the risk score model. A total of 85 patients in the validating set underwent a pathology biopsy of level Ib lymph nodes to test the model. The remaining 327 patients from the prognostic-research set were used to evaluate the prognostic impact of level Ib irradiation in high- and low-risk groups. The independent risk factors in the model were carotid sheath involvement, the maximal diameter of the neck lymph nodes (?20 mm) and the involvement of the level II/III/IV lymph nodes. The involvement of level IV was assigned score 2 and the other risk factors were assigned score 1. According to the total scores, the patients were divided into the low- (total score, 0-1; level Ib metastasis rate, 0.5%) and high-risk groups (total score, 2-4; level Ib metastasis rate, 8.5%). In the validating set, the metastatic rate of level Ib in 43 low-risk patients was 0%, and the rate was 31.0% (13/42) in 42 high-risk patients. In the prognostic-research set, the prognosis of 137 low-risk patients was not affected by level Ib irradiation. However, level Ib unirradiation was an independent prognostic factor for the locoregional recurrence in 190 high-risk patients. According to the data, the novel score model could help assess the metastatic risk of level Ib in primary NPC, and the radiotherapy on level Ib may impact the locoregional recurrence in high-risk patients.
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A new continuous cell line from Blaps rhynchoptera Fairmaire (Coleoptera: Tenebrionidae).
In Vitro Cell. Dev. Biol. Anim.
PUBLISHED: 04-10-2014
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The first continuous cell line from the neonate larval tissues of Blaps rhynchoptera, which has been used as a folk medicine in Yunnan Province, China, was established and designated RIRI-BR1. This cell line was serially subcultured in Schneider's medium supplemented with 15% fetal bovine serum (FBS). The cells grew adherent to culture flasks and exhibited spindle-like and polygonal shapes. The growth rate was determined at the 50th passage, and the population doubling time was calculated to be 79.5 h. The post-thaw viability of the cell line at different passages showed that the cells from higher passages could be recovered easier after cryopreservation than the cells from lower passages. The average chromosome numbers from cells of the RIRI-BR1 cell line at passages 5 to 50 ranged from 12 to 130. The rDNA internal transcribed spacer (ITS) sequence analysis indicated that the RIRI-BR1 cell line was derived from B. rhynchoptera.
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ERK1/2 antagonize AMPK-dependent regulation of Fc?RI-mediated mast cell activation and anaphylaxis.
J. Allergy Clin. Immunol.
PUBLISHED: 03-26-2014
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Extracellular signal-regulated kinases 1/2 (ERK1/2) make important contributions to allergic responses via their regulation of degranulation, eicosanoid production, and cytokine expression by mast cells, yet the mechanisms underlying their positive effects on Fc?RI-dependent signaling are not fully understood. Recently, we reported that mast cell activation and anaphylaxis are negatively regulated by AMP-activated protein kinase (AMPK). However, little is known about the relationship between ERK1/2-mediated positive and the AMPK-mediated negative regulation of Fc?RI signaling in mast cells.
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Britanin Suppresses IgE/Ag-Induced Mast Cell Activation by Inhibiting the Syk Pathway.
Biomol Ther (Seoul)
PUBLISHED: 03-25-2014
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The aim of this study was to determine whether britanin, isolated from the flowers of Inula japonica (Inulae Flos), modulates the generation of allergic inflammatory mediators in activated mast cells. To understand the biological activity of britanin, the authors investigated its effects on the generation of prostaglandin D2 (PGD2), leukotriene C4 (LTC4), and degranulation in IgE/Ag-induced bone marrow-derived mast cells (BMMCs). Britanin dose dependently inhibited degranulation and the generations of PGD2 and LTC4 in BMMCs. Biochemical analyses of IgE/Ag-mediated signaling pathways demonstrated that britanin suppressed the phosphorylation of Syk kinase and multiple downstream signaling processes, including phospholipase C?1 (PLC?1)-mediated calcium influx, the activation of mitogen-activated protein kinases (MAPKs; extracellular signal-regulated kinase 1/2, c-Jun NH2-terminal kinase and p38), and the nuclear factor-?B (NF-?B) pathway. Taken together, the findings of this study suggest britanin suppresses degranulation and eicosanoid generation by inhibiting the Syk-dependent pathway and britanin might be useful for the treatment of allergic inflammatory diseases.
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The complex jujube genome provides insights into fruit tree biology.
Nat Commun
PUBLISHED: 03-21-2014
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The jujube (Ziziphus jujuba Mill.), a member of family Rhamnaceae, is a major dry fruit and a traditional herbal medicine for more than one billion people. Here we present a high-quality sequence for the complex jujube genome, the first genome sequence of Rhamnaceae, using an integrated strategy. The final assembly spans 437.65?Mb (98.6% of the estimated) with 321.45?Mb anchored to the 12 pseudo-chromosomes and contains 32,808 genes. The jujube genome has undergone frequent inter-chromosome fusions and segmental duplications, but no recent whole-genome duplication. Further analyses of the jujube-specific genes and transcriptome data from 15 tissues reveal the molecular mechanisms underlying some specific properties of the jujube. Its high vitamin C content can be attributed to a unique high level expression of genes involved in both biosynthesis and regeneration. Our study provides insights into jujube-specific biology and valuable genomic resources for the improvement of Rhamnaceae plants and other fruit trees.
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Population impact of a high cardiovascular risk management program delivered by village doctors in rural China: design and rationale of a large, cluster-randomized controlled trial.
BMC Public Health
PUBLISHED: 03-16-2014
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The high-risk strategy has been proven effective in preventing cardiovascular disease; however, the population benefits from these interventions remain unknown. This study aims to assess, at the population level, the effects of an evidence-based high cardiovascular risk management program delivered by village doctors in rural China.
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Sequence analysis of mitochondrial ND1 gene can reveal the genetic structure and origin of Bactrocera dorsalis s.s.
BMC Evol. Biol.
PUBLISHED: 03-14-2014
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The oriental fruit fly, Bactrocera dorsalis s.s., is one of the most important quarantine pests in many countries, including China. Although the oriental fruit fly has been investigated extensively, its origins and genetic structure remain disputed. In this study, the NADH dehydrogenase subunit 1 (ND1) gene was used as a genetic marker to examine the genetic diversity, population structure, and gene flow of B. dorsalis s.s. throughout its range in China and southeast Asia.
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Expression of genomic functional estrogen receptor 1 in mouse sertoli cells.
Reprod Sci
PUBLISHED: 03-10-2014
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There is no consensus whether Sertoli cells express estrogen receptor 1 (Esr1). Reverse transcription-polymerase chain reaction, Western blot, and immunofluorescence demonstrated that mouse Sertoli cell lines, TM4, MSC-1, and 15P-1, and purified primary mouse Sertoli cells (PSCs) contained Esr1 messenger RNA and proteins. Incubation of Sertoli cells with 17?-estradiol (E2) or ESR1 agonist stimulated the expression of an estrogen responsive gene Greb1, which was prevented by ESR inhibitor or ESR1 antagonist. Overexpression of Esr1 in MSC-1 enhanced E2-induced Greb1 expression, while knockdown of Esr1 by small interfering RNA in TM4 attenuated the response. Furthermore, E2-induced Greb1 expression was abolished in the PSCs isolated from Amh-Cre/Esr1-floxed mice in which Esr1 in Sertoli cells were selectively deleted. Chromatin immunoprecipitation assays indicated that E2-induced Greb1 expression in Sertoli cells was mediated by binding of ESR1 to estrogen responsive elements. In summary, ligand-dependent nuclear ESR1 was present in mouse Sertoli cells and mediates a classical genomic action of estrogens.
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Curcumin inhibits the activation of immunoglobulin e-mediated mast cells and passive systemic anaphylaxis in mice by reducing serum eicosanoid and histamine levels.
Biomol Ther (Seoul)
PUBLISHED: 03-06-2014
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Curcumin is naturally occurring polyphenolic compound found in turmeric and has many pharmacological activities. The present study was undertaken to evaluate anti-allergic inflammatory activity of curcumin, and to investigate its inhibitory mechanisms in immunoglobulin E (IgE)/Ag-induced mouse bone marrow-derived mast cells (BMMCs) and in a mouse model of IgE/Ag-mediated passive systemic anaphylaxis (PSA). Curcumin inhibited cyclooxygenase-2 (COX-2) dependent prostaglandin D2 (PGD2) and 5-lipoxygenase (5-LO) dependent leukotriene C4 (LTC4) generation dose-dependently in BMMCs. To probe the mechanism involved, we assessed the effects of curcumin on the phosphorylation of Syk and its downstream signal molecules. Curcumin inhibited intracellular Ca(2+) influx via phospholipase C?1 (PLC?1) activation and the phosphorylation of mitogen-activated protein kinases (MAPKs) and the nuclear factor-?B (NF-?B) pathway. Furthermore, the oral administration of curcumin significantly attenuated IgE/Ag-induced PSA, as determined by serum LTC4, PGD2, and histamine levels. Taken together, this study shows that curcumin offers a basis for drug development for the treatment of allergic inflammatory diseases.
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Cytogenetic and genetic mutation features of de novo acute myeloid leukemia in elderly Chinese patients.
Asian Pac. J. Cancer Prev.
PUBLISHED: 02-27-2014
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The present study aimed to examine the cytogenetic and genetic mutation features of acute myeloid leukemia (AML) in elderly Chinese patients.
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Slide fastener reduction of graphene-oxide edges by calcium: insight from ab initio molecular dynamics.
Chemphyschem
PUBLISHED: 02-20-2014
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The reduction of graphene oxide can be used as a simple way to produce graphene on a large scale. However, the numerous edges produced by the oxidation of graphite seriously degrade the quality of the graphene and its carrier transport property. In this work, the reduction of oxygen-passivated graphene edges and the subsequent linking of separated graphene sheets by calcium are investigated by using first-principles calculations. The calculations show that calcium can effectively remove the oxygen groups from two adjacent edges. The joining point of the edges serves as the starting point of the reduction and facilitates the reaction. Once the oxygen groups are removed, the crack is sutured. If the joining point is lacking, it becomes difficult to zip the separated fragments. A general electron-reduction model and a random atom-reduction model are suggested for these two situations. The present study sheds light on the reduction of graphene-oxide edges by using reactive metals to give large-sized graphene through a simple chemical reaction.
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Four new quassinoids from the roots of Eurycoma longifolia Jack.
Fitoterapia
PUBLISHED: 02-12-2014
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Seven compounds were isolated from the roots of Eurycoma longifolia, and characterized by comprehensive analysis of 1D and 2D NMR experiments along with single crystal X-ray diffraction. Among them, four new quassinoids were identified and three of them were diastereomers for each other. Compounds 1-7 were evaluated for cytotoxicities against HT-29, MCF-7, LOVO, BGC-823, MGC-803, HepG2, HeLa, and A549 cancer cell lines. Compounds 2 and 5 exhibited the lowest IC50 values of 24.9 ?M, 11.8 ?M, and 44.1 ?M, 14.1 ?M towards MCF-7, MGC-803 cancer cell lines, respectively, while compound 6 exhibited moderate cytotoxicity towards all the selected cancer cell lines.
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Clozapine for treatment-resistant bipolar disorder: a systematic review.
Bipolar Disord
PUBLISHED: 02-11-2014
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To evaluate the efficacy and safety of clozapine for treatment-resistant bipolar disorder (TRBD).
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Poly(?-caprolactone) scaffolds of highly controlled porosity and interconnectivity derived from co-continuous polymer blends: model bead and cell infiltration behavior.
J Mater Sci Mater Med
PUBLISHED: 02-06-2014
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Porous structures destined for tissue engineering applications should ideally show controlled and narrow pore size distributions with fully interconnected pores. This study focuses on the development of novel poly(?-caprolactone) (PCL) structures with fully connected pores of 84, 116, 141, and 162 ?m average diameter, from melt blending of PCL with poly(ethylene oxide) (PEO) at the co-continuous composition, followed by static annealing and selective extraction of PEO. Our results demonstrate a low onset concentration for PEO continuity and a broad region of phase inversion. A novel in vitro assay was used to compare scaffold infiltration by 10-?m diameter polystyrene beads intended to mimic trypsinized human bone marrow stromal cells (hBMSCs). Beads showed a linear increase in the extent of scaffold infiltration with increasing pore size, whereas BMSCs infiltrated 162 and 141 ?m pores, below which the cells aggregated and adhered near the seeding area with low infiltration into the porous device. While providing a baseline for non-aggregated systems, the beads closely mimic trypsinized cells at pore sizes equal to or larger than 141 ?m, where optimal retention and distribution of hBMSCs are detected. A cytotoxicity assay using L929 cells showed that these scaffolds were cytocompatible and no cell necrosis was detected. This study shows that a melt blending approach produces porous PCL scaffolds of highly controlled pore size, narrow size distribution and complete interconnectivity, while the bead model system reveals the baseline potential for a homogeneous, non-aggregated distribution of hBMSCs at all penetration depths.
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Calcium channel autoantibodies predicted sudden cardiac death and all-cause mortality in patients with ischemic and nonischemic chronic heart failure.
Dis. Markers
PUBLISHED: 02-04-2014
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The purpose of this study was to evaluate whether CC-AAbs levels could predict prognosis in CHF patients. A total of 2096 patients with CHF (841 DCM patients and 1255 ICM patients) and 834 control subjects were recruited. CC-AAbs were detected and the relationship between CC-AAbs and patient prognosis was analyzed. During a median follow-up time of 52 months, there were 578 deaths. Of these, sudden cardiac death (SCD) occurred in 102 cases of DCM and 121 cases of ICM. The presence of CC-AAbs in patients was significantly higher than that of controls (both P < 0.001). Multivariate analysis revealed that positive CC-AAbs could predict SCD (HR 3.191, 95% CI 1.598-6.369 for DCM; HR 2.805, 95% CI 1.488-5.288 for ICM) and all-cause mortality (HR 1.733, 95% CI 1.042-2.883 for DCM; HR 2.219, 95% CI 1.461-3.371 for ICM) in CHF patients. A significant association between CC-AAbs and non-SCD (NSCD) was found in ICM patients (HR = 1.887, 95% CI 1.081-3.293). Our results demonstrated that the presence of CC-AAbs was higher in CHF patients versus controls and corresponds to a higher incidence of all-cause death and SCD. Positive CC-AAbs may serve as an independent predictor for SCD and all-cause death in these patients.
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A genome-wide association study of limb bone length using a Large White?×?Minzhu intercross population.
Genet. Sel. Evol.
PUBLISHED: 01-28-2014
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In pig, limb bone length influences ham yield and body height to a great extent and has important economic implications for pig industry. In this study, an intercross population was constructed between the indigenous Chinese Minzhu pig breed and the western commercial Large White pig breed to examine the genetic basis for variation in limb bone length. The aim of this study was to detect potential genetic variants associated with porcine limb bone length.
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Referral by outreach specialist reduces hospitalisation costs of rural patients with digestive tract cancer: a report from medical consortium in China.
Rural Remote Health
PUBLISHED: 01-14-2014
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The authors examined the effect of referrals from outreach specialists on total hospitalisation costs of rural Chinese patients receiving surgical treatment for digestive tract cancer at a tertiary hospital within a vertically integrated medical consortium.
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Childhood trauma associates with clinical features of bipolar disorder in a sample of Chinese patients.
J Affect Disord
PUBLISHED: 01-13-2014
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Childhood trauma is a major public health problem which has a long-term consequence, a few studies have examined the relationship between childhood trauma and clinical features of bipolar disorder, most in western culture, with no such studies done in Chinese culture.
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Prevalence and predictors of decreased glomerular filtration rate in tibetan children with congenital heart disease.
Indian J Pediatr
PUBLISHED: 01-13-2014
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To assess the prevalence of decreased glomerular filtration rate (GFR) in Tibetan children with congenital heart disease (CHD) and its associated risk factors.
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Genome-wide identification, phylogenetic analysis, expression profiling, and protein-protein interaction properties of TOPLESS gene family members in tomato.
J. Exp. Bot.
PUBLISHED: 01-07-2014
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Members of the TOPLESS gene family emerged recently as key players in gene repression in several mechanisms, especially in auxin perception. The TOPLESS genes constitute, in 'higher-plant' genomes, a small multigenic family comprising four to 11 members. In this study, this family was investigated in tomato, a model plant for Solanaceae species and fleshy fruits. Six open reading frames predicted to encode topless-like proteins (SlTPLs) containing the canonical domains (LisH, CTLH, and two WD40 repeats) were identified in the tomato genome. Nuclear localization was confirmed for all members of the SlTPL family with the exception SlTPL6, which localized at the cytoplasm and was excluded from the nucleus. SlTPL genes displayed distinctive expression patterns in different tomato organs, with SlTPL1 showing the highest levels of transcript accumulation in all tissues tested except in ripening fruit where SlTPL3 and SlTPL4 were the most prominently expressed. To gain insight into the specificity of the different TOPLESS paralogues, a protein-protein interaction map between TOPLESS and auxin/indole-3-acetic acid (Aux/IAA) proteins was built using a yeast two-hybrid approach. The PPI map enabled the distinction of two patterns: TOPLESS isoforms interacting with the majority of Aux/IAA, and isoforms with limited capacity for interaction with these protein partners. Interestingly, evolutionary analyses of the TOPLESS gene family revealed that the highly expressed isoforms (SlTPL1, SlTPL3, and SlTPL4) corresponded to the three TPL-related genes undergoing the strongest purifying selection, while the selection was much weaker for SlTPL6, which was expressed at a low level and encoded a protein lacking the capacity to interact with Aux/IAAs.
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High-mobility Bi2Se3 nanoplates manifesting quantum oscillations of surface states in the sidewalls.
Sci Rep
PUBLISHED: 01-03-2014
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Magnetotransport measurements of topological insulators are very important to reveal the exotic topological surface states for spintronic applications. However, the novel properties related to the surface Dirac fermions are usually accompanied by a large linear magnetoresistance under perpendicular magnetic field, which makes the identification of the surface states obscure. Here, we report prominent Shubnikov-de Haas (SdH) oscillations under an in-plane magnetic field, which are identified to originate from the surface states in the sidewalls of topological insulator Bi2Se3 nanoplates. Importantly, the SdH oscillations appear with a dramatically weakened magnetoresistance background, offering an easy path to probe the surface states directly when the coexistence of surface states and bulk conduction is inevitable. Moreover, under a perpendicular magnetic field, the oscillations in Hall conductivity have peak-to-valley amplitudes of 2?e(2)/h, giving confidence to achieve a quantum Hall effect in this system. A cross-section view of the nanoplate shows that the sidewall is (015) facet dominant and therefore forms a 58° angle with regard to the top/bottom surface instead of being perpendicular; this gives credit to the surface states' behavior as two-dimensional transport.
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Regenerating gene family member 4 promotes growth and migration of gastric cancer through protein kinase B pathway.
Int J Clin Exp Med
PUBLISHED: 01-01-2014
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Regenerating gene family member 4 (REG4), a secreted protein, is overexpressed in several cancers, including gastric cancer. The present study was undertaken to determine the roles of REG4 in the growth of gastric cancer in the nude mice and in the proliferation and migration in human gastric cancer cell line and its downstream signaling pathway. Gastric cancer models were elicited by intraperitoneally injecting MKN45 human gastric cancer cells and the tumor size was measured every other day. The expressions of REG4 mRNA and protein were increased in the gastric cancer tissues from gastric cancer patients. REG4 increased the gastric tumor weight and size in the nude mice, and promoted the proliferation and migration of gastric cancer cells MKN45. Adeno-associated viral (AAV)-mediated knockdown of REG4 decreased the gastric tumor weight and size in the nude mice, and suppressed the proliferation and migration of MKN45 cells. REG4 increased the expression of phosphorylated protein kinase B (Akt). Triciribine hydrate (TCN), the inhibitor of Akt, decreased the gastric tumor weight and size in the nude mice and abolished REG4-induced weight and size increase of the tumor. TCN also inhibited proliferation and migration and abolished REG4-induced proliferation and migration increase of human gastric cell line MKN45. These results indicate that REG4 promotes the growth, proliferation and migration of gastric cancer through Akt pathway.
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Using a Low-Sodium, High-Potassium Salt Substitute to Reduce Blood Pressure among Tibetans with High Blood Pressure: A Patient-Blinded Randomized Controlled Trial.
PLoS ONE
PUBLISHED: 01-01-2014
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To evaluate the effects of a low-sodium and high-potassium salt-substitute on lowering blood pressure (BP) among Tibetans living at high altitude (4300 meters).
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LC3B-II deacetylation by histone deacetylase 6 is involved in serum-starvation-induced autophagic degradation.
Biochem. Biophys. Res. Commun.
PUBLISHED: 10-30-2013
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Autophagy is a conserved mechanism for controlling the degradation of misfolded proteins and damaged organelles in eukaryotes and can be induced by nutrient withdrawal, including serum starvation. Although differential acetylation of autophagy-related proteins has been reported to be involved in autophagic flux, the regulation of acetylated microtubule-associated protein 1 light chain 3 (LC3) is incompletely understood. In this study, we found that the acetylation levels of phosphotidylethanolamine (PE)-conjugated LC3B (LC3B-II), which is a critical component of double-membrane autophagosome, were profoundly decreased in HeLa cells upon autophagy induction by serum starvation. Pretreatment with lysosomal inhibitor chloroquine did not attenuate such deacetylation. Under normal culture medium, we observed increased levels of acetylated LC3B-II in cells treated with tubacin, a specific inhibitor of histone deacetylase 6 (HDAC6). However, tubacin only partially suppressed serum-starvation-induced LC3B-II deacetylation, suggesting that HDAC6 is not the only deacetylase acting on LC3B-II during serum-starvation-induced autophagy. Interestingly, tubacin-induced increase in LC3B-II acetylation was associated with p62/SQSTM1 accumulation upon serum starvation. HDAC6 knockdown did not influence autophagosome formation but resulted in impaired degradation of p62/SQSTM1 during serum starvation. Collectively, our data indicated that LC3B-II deacetylation, which was partly mediated by HDAC6, is involved in autophagic degradation during serum starvation.
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ART1 Silencing Enhances Apoptosis of Mouse CT26 Cells via the PI3K/Akt/NF-?B Pathway.
Cell. Physiol. Biochem.
PUBLISHED: 10-28-2013
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Background/Aims: Colorectal carcinoma is one of the most common cancers world-wide, with high morbidity and mortality rates. Arginine ADP-ribosyltransferase 1(ART1) is an important ecto-ADP-ribose transferase and has been proven to be intimately involved in a number of biological processes. However, the influence of ART1 on survival and apoptosis of colorectal carcinoma cells and the potential mechanism of action of ART1 remain uncharacterized. Methods: ART1 was silenced via lentiviral vector-mediated short hairpin RNA (shRNA) in CT26 colon carcinoma cells, and cisplatin (CDDP) was applied to induce apoptosis. Survival and apoptosis rate of CT26 cells was assessed by CCK8 assay, flow cytometry and Hoechst 33342 staining. Expression and activity of signaling proteins were detected by Western blot. Results: ART1 knockdown enhanced the inhibition of cell survival and increased the apoptosis induced by CDDP. Furthermore, the reduced survival rate correlated with reduced levels of phos-Akt(Thr308) and phos-I?B? and reduced NF-?B p65 nuclear translocation. A decline in Bcl-2 and Bcl-xl expression and an increase in Bax expression may explain the enhanced apoptosis. Conclusion: This study provides a molecular mechanism for the function of ART1 in colorectal carcinoma and defines a potential therapeutic target for the enhanced treatment of this prominent world-wide disease. © 2014 S. Karger AG, Basel.
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MRI diagnosis of perivascular epithelioid cell tumor (PEComa) of the liver.
Rom J Morphol Embryol
PUBLISHED: 09-27-2013
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Perivascular epithelioid cell tumor (PEComa) has been rarely reported in the liver.
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Two-dimensional transition metal honeycomb realized: Hf on Ir(111).
Nano Lett.
PUBLISHED: 09-10-2013
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Two-dimensional (2D) honeycomb systems made of elements with d electrons are rare. Here, we report the fabrication of a transition metal (TM) 2D layer, namely, hafnium crystalline layers on Ir(111). Experimental characterization reveals that the Hf layer has its own honeycomb lattice, morphologically identical to graphene. First-principles calculations provide evidence for directional bonding between adjacent Hf atoms, analogous to carbon atoms in graphene. Calculations further suggest that the freestanding Hf honeycomb could be ferromagnetic with magnetic moment ?/Hf = 1.46 ?(B). The realization and investigation of TM honeycomb layers extend the scope of 2D structures and could bring about novel properties for technological applications.
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Enhancement of terahertz radiation from GaP emitters by subwavelength antireflective micropyramid structures.
Opt Lett
PUBLISHED: 08-14-2013
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Subwavelength antireflective micropyramid structures, designed by rigorous coupled-wave analysis and fabricated by precision micromachining, are used to enhance the terahertz (THz) radiation output of optical rectification in GaP crystal-based emitters. An average 16% increase in the THz radiation power emitted by a 3 mm GaP crystal is experimentally demonstrated using an antireflective micropyramid grating with a period of 60 ?m and a base angle of 55.5°. Optimized pyramidal-frustum gratings are shown to operate as highly efficient antireflective structures within an ultrabroadband range of 0.5-5 THz.
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Codon usage patterns in Chinese bayberry (Myrica rubra) based on RNA-Seq data.
BMC Genomics
PUBLISHED: 07-23-2013
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Codon usage analysis has been a classical topic for decades and has significances for studies of evolution, mRNA translation, and new gene discovery, etc. While the codon usage varies among different members of the plant kingdom, indicating the necessity for species-specific study, this work has mostly been limited to model organisms. Recently, the development of deep sequencing, especial RNA-Seq, has made it possible to carry out studies in non-model species.Result: RNA-Seq data of Chinese bayberry was analyzed to investigate the bias of codon usage and codon pairs. High frequency codons (AGG, GCU, AAG and GAU), as well as low frequency ones (NCG and NUA codons) were identified, and 397 high frequency codon pairs were observed. Meanwhile, 26 preferred and 141 avoided neighboring codon pairs were also identified, which showed more significant bias than the same pairs with one or more intervening codons. Codon patterns were also analyzed at the plant kingdom, organism and gene levels. Changes during plant evolution were evident using RSCU (relative synonymous codon usage), which was even more significant than GC3s (GC content of 3rd synonymous codons). Nine GO categories were differentially and independently influenced by CAI (codon adaptation index) or GC3s, especially in Molecular function category. Within a gene, the average CAI increased from 0.720 to 0.785 in the first 50 codons, and then more slowly thereafter. Furthermore, the preferred as well as avoided codons at the position just following the start codon AUG were identified and discussed in relation to the key positions in Kozak sequences.
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A gold nanoparticles enhanced surface plasmon resonance immunosensor for highly sensitive detection of ischemia-modified albumin.
Sensors (Basel)
PUBLISHED: 07-18-2013
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In this study a novel sensitive nanogold particle sensor enhancement based on mixed self-assembled monolayers was explored and used to construct a Surface Plasmon Resonance (SPR) immunosensor to detect Ischemia Modified Albumin (IMA). Compared with a direct binding SPR assay at a limit of detection (LOD) of 100 ng/L, gold nanoparticles (AuNPs) of 10 nm dramatically improved the LOD of IMA to 10 ng/L. Meanwhile, no interfering substance that may lead to false positive results was identified. These results suggested that the SPR biosensor presented superior properties, and provided a simple label-free strategy to increase assay sensitivity for further acute coronary syndrome (ACS) diagnosis.
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Human antibody neutralizes severe Fever with thrombocytopenia syndrome virus, an emerging hemorrhagic Fever virus.
Clin. Vaccine Immunol.
PUBLISHED: 07-17-2013
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Severe fever with thrombocytopenia syndrome virus (SFTSV), a newly discovered member of the Bunyaviridae family, is the causative agent of an emerging hemorrhagic fever, SFTS, in China. Currently, there are no vaccines or effective therapies against SFTS. In this study, a combinatorial human antibody library was constructed from the peripheral lymphocytes of 5 patients who had recovered from SFTS. The library was screened against purified virions for the production of single-chain variable-region fragments (ScFv). Of the 6 positive clones, one clone (monoclonal antibody [MAb] 4-5) showed neutralizing activity against SFTSV infection in Vero cells. MAb 4-5 was found to effectively neutralize all of the clinical isolates of SFTSV tested, which were isolated from patients in China from 2010 to 2012. MAb 4-5 was found to bind a linear epitope in the ectodomain of glycoprotein Gn. Its neutralizing activity is attributed to blockage of the interactions between the Gn protein and the cellular receptor, indicating that inhibition of virus-cell attachment is its main mechanism. These data suggest that MAb 4-5 can be used as a promising candidate molecule for immunotherapy against SFTSV infection.
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Pinusolide improves high glucose-induced insulin resistance via activation of AMP-activated protein kinase.
Biochem. Biophys. Res. Commun.
PUBLISHED: 06-12-2013
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Adenosine monophosphate (AMP)-activated protein kinase (AMPK) plays a crucial role in the maintenance of cellular energy homeostasis, and several natural compounds that activate AMPK possibly enhance glucose uptake by muscle cells. In this study, we found that pinusolide stimulated AMPK phosphorylation and glucose uptake and these effects were significantly reduced by siRNA LKB1 or compound C, suggesting that enhanced glucose uptake by pinusolide is predominantly accomplished via an LKB1-mediated AMPK activation pathway. An insulin resistance state was induced by exposing cells to 30mM glucose, as indicated by reduced insulin-stimulated tyrosine phosphorylation of IRS-1 and glucose uptake. Under these conditions, the phosphorylation of AMPK and ACC were decreased. Surprisingly, disrupted insulin signaling and decreased AMPK activity by high glucose concentrations were prevented by pinusolide. Moreover, this treatment increased insulin-stimulated glucose uptake via AMPK activation. Taken together, our findings suggest a link between high glucose and insulin resistance in muscle cells, and provide further evidence that pinusolide attenuates blockade of insulin signaling by enhancing IRS-1 tyrosine phosphorylation by the activating the AMPK pathway. In addition, this study indicates the targeting of AMPK represents a new therapeutic strategy for hyperglycemia-induced insulin resistance and type 2 diabetes.
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Systematic combination screening reveals synergism between rapamycin and sunitinib against human lung cancer.
Cancer Lett.
PUBLISHED: 06-04-2013
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Mammalian target of rapamycin (mTOR) acts as a hub integrating signals from nutrient availability and growth factors and plays central roles in regulating protein synthesis and cell growth, which has been validated as a promising target for cancer therapy. Rapamycin and its analogues have emerged as the first generation of mTOR inhibitors, but their efficacy is modest in clinical settings. Combinatorial use of rapamycin with other drugs is a promising strategy to improve its anticancer activity. Here we developed an unbiased systematic binary screening platform aiming to discover new remedy for rapamycin-based cancer therapy. We found that sunitinib emerged as one of the clinically available anticancer drugs screened that displayed significant synergy with rapamycin in NSCLC cells. Combination of rapamycin with sunitinib resulted in enhanced cell cycle arrest in G1 phase, which was accompanied with enhanced suppression of mTOR signaling and disruption of the negative feedback loop that activate AKT upon mTORC1 inhibition. Furthermore, sunitinib and rapamycin displayed synergistic activity against tube formation by human microvessel endothelial cells as well as outgrowth of endothelial tubes and microvessels both in vitro and in vivo, which is associated with down-regulation of VEGF secretion and HIF1? expression. Our study demonstrated that new combinatorial regimen could be identified via systematic drug combination screening and established a mechanistic rationale for a combination approach using rapalogs and sunitinib in the treatment of human NSCLC.
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School connectedness and problematic internet use in adolescents: a moderated mediation model of deviant peer affiliation and self-control.
J Abnorm Child Psychol
PUBLISHED: 05-23-2013
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Although a growing body of research documents the negative association between school connectedness and adolescent problematic Internet use (PIU), little is known about the mediating mechanism (i.e., how school connectedness relates to PIU?) and moderating mechanism (i.e., when the protection is most potent?) underlying this relation. The present study examined whether deviant peer affiliation mediated the relationship between school connectedness and PIU, and whether this mediating process was moderated by adolescent self-control. A total of 2,758 Chinese adolescents (46 % male; mean age?=?13.53 years, SD?=?1.06) from 10 middle schools completed anonymous questionnaires regarding school connectedness, deviant peer affiliation, self-control, and PIU. After controlling for gender, age, socioeconomic status, and parental attachment, it was found that the negative association between school connectedness and adolescent PIU was partially mediated by deviant peer affiliation. Moreover, this indirect link was stronger for adolescents with low self-control than for those with high self-control. These findings underscore the importance of integrating the social control theory and organism-environment interaction model to understand how and when school connectedness impacts adolescent PIU.
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Vaccination inhibits TLR2 transcription via suppression of GR nuclear translocation and binding to TLR2 promoter in porcine lung infected with Mycoplasma hyopneumoniae.
Vet. Microbiol.
PUBLISHED: 05-21-2013
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Toll-like receptors (TLRs) and glucocorticoid receptor (GR) act respectively as effectors of innate immune and stress responses. The crosstalk between them is critical for the maintenance of homeostasis during the immune response. Vaccination is known to boost adaptive immunity, yet it remains elusive whether vaccination may affect GR/TLR interactions following infection. Duroc×Meishan crossbred piglets were allocated to three groups. The control group (CC) received neither vaccination nor infection; the non-vaccinated infection group (NI) was artificially infected intratracheally with Mycoplasma hyopneumoniae (M. hyopneumoniae); while the vaccinated, infected group (VI) was vaccinated intramuscularly with inactivated M. hyopneumoniae one month before infection. The clinical signs and macroscopic lung lesions were significantly reduced by vaccination. However, vaccination did not affect the concentration of M. hyopneumoniae DNA in the lung. Serum cortisol was significantly decreased in both NI and VI pigs (P<0.01), but only VI pigs demonstrated significantly diminished nuclear GR content. TLRs 1-10 were all expressed in lung, among which TLR2 was the most abundant and was significantly up-regulated (P<0.05) in NI pigs, but not in VI pigs. Accordingly, GR binding to the GR response element on TLR2 promoter was significantly increased (P<0.05) in NI pigs, but not in VI pigs. These results suggest that the inhibition of GR nuclear translocation and binding to the TLR2 promoter, which results in diminished TLR2 expression, is associated with the protective effect of vaccination on M. hyopneumoniae-induced lung lesions in the pig.
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Low molecular weight fucoidan improves endoplasmic reticulum stress-reduced insulin sensitivity through AMP-activated protein kinase activation in L6 myotubes and restores lipid homeostasis in a mouse model of type 2 diabetes.
Mol. Pharmacol.
PUBLISHED: 05-08-2013
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Low molecular weight fucoidan (LMWF) is widely used to treat metabolic disorders, but its physiologic effects have not been well determined. In the present study, we investigated the metabolic effects of LMWF in obese diabetic mice (leptin receptor-deficient db/db mice) and the underlying molecular mechanisms involved in endoplasmic reticulum (ER) stress-responsive L6 myotubes. The effect of LMWF-mediated AMP-activated protein kinase (AMPK) activation on insulin resistance via regulation of the ER stress-dependent pathway was examined in vitro and in vivo. In db/db mice, LMWF markedly reduced serum glucose, triglyceride, cholesterol, and low-density lipoprotein levels, and gradually reduced body weights by reducing lipid parameters. Furthermore, it effectively ameliorated glucose homeostasis by elevating glucose tolerance. In addition, the phosphorylation levels of AMPK and Akt were markedly reduced by ER stressor, and subsequently, glucose uptake and fatty acid oxidation were also reduced. However, these adverse effects of ER stress were significantly ameliorated by LMWF. Finally, in L6 myotubes, LMWF markedly reduced the ER stress-induced upregulation of the mammalian target of rapamycin-p70S61 kinase network and subsequently improved the action of insulin via AMPK stimulation. Our findings suggest that AMPK activation by LMWF could prevent metabolic diseases by controlling the ER stress-dependent pathway and that this beneficial effect of LMWF provides a potential therapeutic strategy for ameliorating ER stress-mediated metabolic dysfunctions.
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Prevalence of atrial fibrillation in China and its risk factors.
Biomed. Environ. Sci.
PUBLISHED: 05-07-2013
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To study the prevalence of atrial fibrillation (AF) and the relation with its risk factors in China.
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CCAAT/enhancer-binding protein ? is involved in the breed-dependent transcriptional regulation of 3?-hydroxysteroid dehydrogenase/?(5)-?(4)-isomerase in adrenal gland of preweaning piglets.
J. Steroid Biochem. Mol. Biol.
PUBLISHED: 04-29-2013
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The enzyme 3?-hydroxysteroid dehydrogenase/?(5)-?(4)-isomerase (3?-HSD) catalyzes the biosynthesis of all steroid hormones. The molecular mechanisms regulating porcine adrenal 3?-HSD expression in different breeds are still poorly understood. In this study, we aimed to compare the expression of 3?-HSD between preweaning purebred Large White (LW) and Erhualian (EHL) piglets and to explore the potential factors regulating 3?-HSD transcription. EHL had significantly higher serum levels of cortisol (P<0.01) and testosterone (P<0.01), which were associated with significantly higher expression of 3?-HSD mRNA (P<0.01) and protein (P<0.05) in the adrenal gland, compared with LW piglets. The 5 flanking region of the porcine 3?-HSD gene showed significant sequence variations between breeds, and the sequence of EHL demonstrated an elevated promoter activity (P<0.05) in luciferase reporter gene assay. Higher adrenal expression of 3?-HSD in EHL was accompanied with higher CCAAT/enhancer binding protein ? (C/EBP?) expression (P<0.05), enriched histone H3 acetylation (P<0.05) and C/EBP? binding to 3?-HSD promoter (P<0.05). In addition, higher androgen receptor (AR) (P=0.06) and lower glucocorticoid receptor (GR) (P<0.05) were detected in EHL. Co-immunoprecipitation analysis revealed interactions of C/EBP? with both AR and GR. These results indicate that the C/EBP? binding to 3?-HSD promoter is responsible, at least in part, for the breed-dependent 3?-HSD expression in adrenal gland of piglets. The sequence variations of 3?-HSD promoter and the interactions of AR and/or GR with C/EBP? may also participate in the regulation.
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Biological activities of extracts from Chinese bayberry (Myrica rubra Sieb. et Zucc.): a review.
Plant Foods Hum Nutr
PUBLISHED: 04-23-2013
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Chinese bayberry (Myrica rubra Sieb. et Zucc.) is a subtropical fruit tree native to China and other Asian countries, and culture of this Myricaceae plant has been recorded in Chinese history for more than 2000 years. Bayberry fruit is delicious with attractive color, flavor, and high economic value. Compared with other berries, bayberry fruit is a rich source of cyanidin-3-glucoside (C3G, e.g., 64.8 mg/100 g fresh weight in Biqi cultivar), which accounts for at least 85 % of the anthocyanins in the fruit. Bayberry is also a plant with high medicinal value since different organs have been used historically as folk medicines. Research efforts suggest bayberry extracts contain antioxidants that exhibit bioactivities counteracting inflammation, allergens, diabetes, cancer, bacterial infection, diarrhea and other health issues. Bayberry compounds have been isolated and characterized to provide a better understanding of the chemical mechanisms underlying the biological activities of bayberry extracts and to elaborate the structure-activity relationships. As the identification of compounds progresses, studies investigating the in vivo metabolism and bioavailability as well as potential toxicity of bayberry extracts in animal models are receiving more attention. In addition, breeding and genetic studies of bayberry with high accumulation of health-benefiting compounds may provide new insight for the bayberry research and industry. This review is focused on the main medicinal properties reported and the possible pharmaceutically active compounds identified in different bayberry extracts.
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VEGF, not VEGFR2, is associated with the angiogenesis effect of mini-TyrRS/mini-TrpRS in human umbilical vein endothelial cells in hypoxia.
Cytotechnology
PUBLISHED: 03-28-2013
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The purpose of this study was to determine the relationship between VEGF and mini-TyrRS/mini-TrpRS in angiogenesis in hypoxic culture and to begin to comprehend their mechanism in angiogenesis. We designed a VEGF gene silencing assay by using lentivirus vectors, and then western blotting was used to determine the protein expression of VEGF, VEGFR2 and pVEGFR2 in three groups in hypoxic culture at 3, 6, 12, or 24 h: (1) untransfected human umbilical vein endothelial cells (HUVECs) (Control); (2) pGCSIL-GFP lentivirus vector-transduced HUVECs (Mock); and (3) pGCSIL-shVEGF lentivirus vector-transduced HUVECs (Experimental). We also detected the effects of mini-TyrRS/mini-TrpRS peptides on HUVEC proliferation, migration and tube formation after lentivirus vector transfection and VEGFR2 antibody injection. The results indicated that expression of the mini-TyrRS protein was increased, whereas that of mini-TrpRS was specifically decreased in hypoxic culture both in control and mock groups. However, this trend in protein levels of mini-TyrRS and mini-TrpRS was lost in the experimental group after transduction with the pGCSIL-shVEGF lentivirus vector. The protein expression of VEGF was increased in hypoxic culture both in control and mock groups. After transduction with the pGCSIL-shVEGF lentivirus vector, the protein level of VEGF was noticeably decreased in the experimental group; however, for VEGFR2, the results showed no significant difference in VEGFR2 protein expression in any of the groups. For pVEGFR2, we found a distinct trend from that seen with VEGF. The protein expression of pVEGFR2 was sharply increased in hypoxic culture in the three groups. The addition of mini-TyrRS significantly promoted proliferation, migration and tube formation of HUVECs, while mini-TrpRS inhibited these processes in both control and mock groups in hypoxic culture. However, these effects disappeared after transduction with the pGCSIL-shVEGF lentivirus vector in the experimental group, but no significant difference was observed after VEGFR2 antibody injection. The protein expression of VEGF is similar to that of mini-TyrRS in hypoxic culture and plays an important role in the mini-TyrRS/mini-TrpRS-stimulated proliferation, migration and tube formation of HUVECs in hypoxia. These results also suggest that the change in mini-TyrRS and mini-TrpRS expression in hypoxic culture is not related to VEGFR2 and that some other possible mechanisms, are involved in the phosphorylation of VEGFR2.
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Saucerneol F inhibits tumor necrosis factor-? and IL-6 production by suppressing Fyn-mediated pathways in Fc?RI-mediated mast cells.
Food Chem. Toxicol.
PUBLISHED: 03-26-2013
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The aim of this study was to investigate the effect of saucerneol F (SF) on the productions of the pro-inflammatory cytokines, TNF-? and IL-6, in IgE/Ag-induced mouse bone marrow-derived mast cells (BMMCs). SF dose-dependently suppressed the transcriptions of these pro-inflammatory cytokines. To identify the molecular mechanisms responsible for these suppressions, we examined the effect of SF on three important transcription factors; activator protein-1 (AP-1), nuclear factor-?B (NF-?B), and STAT5. It was found that SF inhibited the nuclear translocation of the p65 subunit of NF-?B to the nucleus and its DNA-binding ability. SF also attenuated mitogen-activated protein kinase (MAPK)-mediated AP-1 activation and STAT5 activation. Biochemical analysis of Fc?RI-mediated signaling pathways demonstrated that SF inhibited the phosphorylation of Fyn and multiple downstream signaling processes, including Syk, Gab2, and the Akt/IKK/I?B and MAPK pathways. Taken together, our results suggest that SF inhibits the production of pro-inflammatory cytokines by suppressing Fyn kinase-dependent signaling events.
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Parental behavioral and psychological control and problematic internet use among chinese adolescents: the mediating role of self-control.
Cyberpsychol Behav Soc Netw
PUBLISHED: 03-19-2013
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Previous research has reported contradictory effects of parental control on adolescents problematic Internet use (PIU). To reconcile the discrepant findings, the current study examined the differential effects of parental behavioral control (solicitation and restriction) and psychological control (guilt induction, love withdrawal, and authority assertion) on adolescents PIU. The mediating effect of self-control on the relationships between parental control and PIU was also examined. A total of 694 Chinese adolescents (M=13.67 years) completed questionnaire measures of parental behavioral control, psychological control, self-control, and PIU. After adjusting for age, gender, and family financial status, it was found that parental restriction (a form of behavioral control) was negatively associated with PIU, whereas love withdrawal (a form of psychological control) was positively associated with PIU. Increased self-control was associated with decreased PIU, and changes in self-control at least partially mediated the differential effects of parental behavioral and psychological control on PIU. Theoretical and practical implications of these findings are discussed.
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Anti-inflammatory activity of hexane extracts from bones and internal organs of Anguilla japonica suppresses cyclooxygenase-2-dependent prostaglandin D? generation in mast cells and anaphylaxis in mice.
Food Chem. Toxicol.
PUBLISHED: 02-20-2013
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The purpose of this study is to investigate the effects of n-hexane extracts from bones and internal organs of Japanese eel, Anguilla japonica (HEE), on cyclooxygenase-2 (COX-2)-dependent prostaglandin D?(PGD?) generation in stem cell factor (SCF), IL-10, plus LPS-induced mouse bone marrow-derived mast cells (BMMCs) and on passive cutaneous anaphylaxis (PCA) in mice. HEE suppressed SCF/IL-10/LPS-induced PGD? generation, and concomitantly reduced COX-2 protein expression dose-dependently. To understand the mechanistic basis for the inhibition of PGD? generation by HEE, we examined the effects of HEE on upstream signaling pathways essential for COX-2 induction. HEE was found to inhibit the translocation of nuclear factor-?B (NF-?B) p65 subunit to the nucleus and its DNA-binding ability through the inhibition of TAK1, IKK and I?B phosphorylation. Furthermore, HEE also attenuated mitogen-activated protein kinase (MAPK)-mediated regulation of DNA binding of activator protein-1 (AP-1). Moreover, oral administration of HEE inhibited anti-dinitrophenyl (DNP) IgE-induced PCA in a dose dependent manner. Taken together, the present study provides new insights into the anti-inflammatory activity of HEE, which could be a promising candidate to be used for an inflammatory therapy.
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Expression of hepatitis B virus 1.3-fold genome plasmid in an SV40 T-antigen-immortalized mouse hepatic cell line.
World J. Gastroenterol.
PUBLISHED: 02-16-2013
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To investigate the expression of the hepatitis B virus (HBV) 1.3-fold genome plasmid (pHBV1.3) in an immortalized mouse hepatic cell line induced by SV40 T-antigen (SV40T) expression.
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AMP-activated protein kinase negatively regulates Fc?RI-mediated mast cell signaling and anaphylaxis in mice.
J. Allergy Clin. Immunol.
PUBLISHED: 02-14-2013
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Aggregation of Fc?RI activates a cascade of signaling events leading to mast cell activation, followed by inhibitory signals that turn off the activating signals. However, the overall view of negative signals in mast cells is still incomplete. Although AMP-activated protein kinase (AMPK), which is generally known as a regulator of energy metabolism, is also associated with anti-inflammation, little is known about the role of AMPK in mast cells.
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MiR-139 inhibits Mcl-1 expression and potentiates TMZ-induced apoptosis in glioma.
CNS Neurosci Ther
PUBLISHED: 02-06-2013
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Mcl-1, an antiapoptotic member of the Bcl-2 family, is overexpressed in human glioblastoma, conferring a survival advantage to tumor cells. The mechanisms underlying its dysregulation have not been clarified. In this study, we explored the involvement of micro-RNAs that acted as endogenous sequence-specific suppressors of gene expression.
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Inhibitory cross-talk between the AMPK and ERK pathways mediates endoplasmic reticulum stress-induced insulin resistance in skeletal muscle.
Br. J. Pharmacol.
PUBLISHED: 02-05-2013
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Endoplasmic reticulum (ER) stress has been implicated in the pathogeneses of insulin resistance and type 2 diabetes, and extracellular signal-regulated kinase (ERK) antagonist is an insulin sensitizer that can restore muscle insulin responsiveness in both tunicamycin-treated muscle cells and type 2 diabetic mice. The present study was undertaken to determine whether the chemical or genetic inhibition ER stress pathway targeting by ERK results in metabolic benefits in muscle cells.
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Characterization, Purification of Poncirin from Edible Citrus Ougan (Citrus reticulate cv. Suavissima) and Its Growth Inhibitory Effect on Human Gastric Cancer Cells SGC-7901.
Int J Mol Sci
PUBLISHED: 01-20-2013
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Poncirin is a bitter flavanone glycoside with various biological activities. Poncirin was isolated from four different tissues (flavedo, albedo, segment membrane, and juice sac) of Ougan fruit (Citrus reticulate cv. Suavissima). The highest content of poncirin was found in the albedo of Ougan fruit (1.37 mg/g DW). High speed counter-current chromatography (HSCCC) combined with D101 resin chromatography was utilized for the separation and purification of poncirin from the albedo of Ougan fruit. After this two-step purification, poncirin purity increased from 0.14% to 96.56%. The chemical structure of the purified poncirin was identified by both HPLC-PDA and LC-MS. Poncirin showed a significant in vitro inhibitory effect on the growth of the human gastric cancer cells, SGC-7901, in a dose-dependent manner. Thus, poncirin from Ougan fruit, may be beneficial for gastric cancer prevention. The purification method demonstrated here will be useful for further studies on the pharmacological mechanism of poncirin activity, as well as for guiding the consumption of Ougan fruit.
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Octreotide promotes weight loss via suppression of intestinal MTP and apoB48 expression in diet-induced obesity rats.
Nutrition
PUBLISHED: 01-11-2013
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The goal of this study was to investigate the effect of octreotide on the expression of intestinal fat absorption-associated apolipoproteinB48 (apoB48), microsomal triglyceride transfer protein (MTP) and apolipoproteinAIV (apoAIV) in a high-fat diet-induced obesity rat model.
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Glyceollin improves endoplasmic reticulum stress-induced insulin resistance through CaMKK-AMPK pathway in L6 myotubes.
J. Nutr. Biochem.
PUBLISHED: 01-11-2013
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Glyceollin has been shown to have antidiabetic properties, although its molecular mechanism is not known. Here, we have investigated the metabolic effects of glyceollin in animal models of insulin resistance and in endoplasmic reticulum (ER) stress-responsive muscle cells. db/db mice were treated with glyceollin for 4weeks and triglycerides, total cholesterol, low-density lipoprotein (LDL) and high-density lipoprotein (HDL) levels were measured. Glyceollin reduced serum insulin and triglycerides and increased HDL levels in db/db mice. Furthermore, glyceollin caused a significant improvement in glucose homeostasis without altering body weight and food intake in db/db mice. In muscle cells, glyceollin increased the activity of AMP-activated protein kinase (AMPK) as well as cellular glucose uptake. Fatty acid oxidation was also increased. In parallel, phosphorylation of acetyl-CoA carboxylase (ACC) at Ser-79 was increased, consistent with decreased ACC activity. An insulin-resistant state was induced by exposing cells to 5?g/ml of tunicamycin as indicated by decreased insulin-mediated tyrosine phosphorylation of insulin receptor substrate-1 (IRS-1) and glucose uptake. Inhibition of insulin-mediated tyrosine phosphorylation of IRS-1 and glucose uptake under ER stress was prevented by glyceollin. Strikingly, glyceollin reduced ER stress-induced, c-Jun NH2-terminal kinase activation and subsequently increased insulin signaling via stimulation of AMPK activity in L6 myotubes. Pharmacologic inhibition or knockdown of Ca(2+)/calmodulin-dependent protein kinase kinase blocked glyceollin-increased AMPK phosphorylation and insulin sensitivity under ER stress conditions. Taken together, these results indicate that glyceollin-mediated enhancement of insulin sensitivity under ER stress conditions is predominantly accomplished by activating AMPK, thereby having beneficial effects on hyperglycemia and insulin resistance.
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Analysis of Expressed Sequence Tags from Chinese Bayberry Fruit (Myrica rubra Sieb. and Zucc.) at Different Ripening Stages and Their Association with Fruit Quality Development.
Int J Mol Sci
PUBLISHED: 01-09-2013
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A total of 2000 EST sequences were produced from cDNA libraries generated from Chinese bayberry fruit (Myrica rubra Sieb. and Zucc. cv. "Biqi") at four different ripening stages. After cluster and assembly analysis of the datasets by UniProt, 395 unigenes were identified, and their presumed functions were assigned to 14 putative cellular roles. Furthermore, a sequence BLAST was done for the top ten highly expressed genes in the ESTs, and genes associated with disease/defense and anthocyanin accumulation were analyzed. Gene-encoding elements associated with ethylene biosynthesis and signal transductions, in addition to other senescence-regulating proteins, as well as those associated with quality formation during fruit ripening, were also identified. Their possible roles were subsequently discussed.
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Establishment and characterization of a cell line developed from the neonate larvae of Papilio demoleus Linnaeus (Lepidoptera: Papilionidae).
In Vitro Cell. Dev. Biol. Anim.
PUBLISHED: 01-09-2013
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A new cell line named RIRI-PaDe, developed from the neonate larvae of Papilio demoleus Linnaeus, was established in modified Graces medium supplemented with 20% fetal bovine serum. The cell line was incubated at 28°C and consisted of attached round and short spindle-like cells. The population doubling time was 55 h. The chromosome numbers varied widely from 24 to 136 with a mode of 59 at the 71st passage. Comparison of mitochondrial cytochrome c oxidase subunit I gene of the cell line and neonate larvae confirmed that the cell line was of P. demoleus origin. This cell line was susceptible to the Autographa californica multicapsid nucleopolyhedrovirus and Apocheima cinerarius nucleopolyhedrovirus.
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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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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.