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Find video protocols related to scientific articles indexed in Pubmed.
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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Chinese Herbal Medicine for Obesity: A Randomized, Double-Blinded, Multicenter, Prospective Trial.
Am. J. Chin. Med.
PUBLISHED: 11-20-2014
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Obesity is a serious medical problem worldwide. As a holistic therapy, traditional Chinese medicine (TCM) may have a potential in obesity management. In this controlled trial, we evaluated the safety and effectiveness of Xin-Ju-Xiao-Gao-Fang (XJXGF), a TCM herbal formulation, in 140 obese subjects over a 24-week period. The XJXGF formula mainly consists of rhubarb, coptis, semen cassia, and citrus aurantium. Subjects with body mass index (BMI) 28-40 kg/m(2) were recruited at 5 centers in China. We assessed the changes in subjects' body weight, its related parameters, and the reduction of insulin resistance (IR) after administration of XJXGF formula or low-dose XJXGF (10% of the XJXGF formula, as control). After 24-week treatment, among participants in the XJXGF formula group and low-dose XJXGF group, the mean ± SE changes in the body weight were -3.58±0.48 and -1.91±0.38 kg, respectively (p < 0.01). The changes in the IR-index of two groups were -2.65±1.04 and -1.58±1.3, respectively (p < 0.05). There were no serious adverse events reported during the 24-week trial. Participants reported 7 minor adverse events, 4 in the XJXGF formula group and 3 in the low-dose XJXGF group (p = 0.578). Future studies are needed to investigate the clinical utility of this TCM formulation in the treatment of obese subjects.
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[Current application of noninvasive ventilation in preterm infants with respiratory distress syndrome.]
Zhongguo Dang Dai Er Ke Za Zhi
PUBLISHED: 11-20-2014
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In order to reduce the serious complications associated with invasive mechanical ventilation, non-invasive ventilation (NIV) has increasingly been chosen as the primary ventilation in preterm infants with respiratory distress syndrome (RDS). In the last 4 decades, nasal continuous positive airway pressure (NCPAP) has been as a main, or even the only mode of NIV in preterm infants with RDS. In the recent decade, improvements in sensors and nasal airway interfaces have resulted in the introduction of a variety of other new types of NIV, such as nasal intermittent positive pressure ventilation (NIPPV), bi-level positive airway pressure (BiPAP). Subsequent studies have shown that some new modes may be more superior to NCPAP in preterm infants with RDS. In order to further understand the application of various NIV modes, we review literatures about all kinds of NIV as a primary mode of ventilation in preterm infants with RDS.
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Proposal for fabrication-tolerant SOI polarization splitter-rotator based on cascaded MMI couplers and an assisted bi-level taper.
Opt Express
PUBLISHED: 11-18-2014
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A novel silicon-on-insulator (SOI) polarization splitter-rotator (PSR) with a large fabrication tolerance is proposed based on cascaded multimode interference (MMI) couplers and an assisted mode-evolution taper. The tapers are designed to adiabatically convert the input TM0 mode into the TE1 mode, which will output as the TE0 mode after processed by the subsequent MMI mode converter, 90-degree phase shifter (PS) and MMI 3 dB coupler. The numerical simulation results show that the proposed device has a < 0.5 dB insertion loss with < -17 dB crosstalk in C optical communication band. Fabrication tolerance analysis is also performed with respect to the deviations of MMI coupler width, PS width, slab height and upper-cladding refractive index, showing that this device could work well even when affected by considerable fabrication errors. With such a robust performance with a large bandwidth, this device offers potential applications for CMOS-compatible polarization diversity, especially in the booming 100 Gb/s coherent optical communications based on silicon photonics technology.
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IKK? is required for the homeostasis of regulatory T cells and for the expansion of both regulatory and effector CD4 T cells.
FASEB J.
PUBLISHED: 11-08-2014
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It was reported that TNF receptor type II signaling, which has the capacity to stimulate CD4(+) forkhead box P3(+) (Foxp3(+)) regulatory T cells (Tregs), activated the noncanonical NF-?B pathway in an IKK?-dependent manner. Therefore, we studied the role of IKK? in the homeostasis of Treg population. To this end, we generated a mouse strain with conditional knockout of IKK? in CD4 cells (Ikk?(f/f):CD4.Cre) that showed a >60% reduction in the number of Tregs in the thymus and peripheral lymphoid tissues, whereas the number of Foxp3(-) effector T cells (Teffs) remained at a normal level. The function of Tregs deficient in IKK? was examined using Rag1(-/-) mice cotransferred with naive CD4 cells (nCD4s). Although wild-type (WT) Tregs inhibited colitis induced by transfer of WT nCD4s, IKK?-deficient Tregs failed to do so, which was associated with their inability to reconstitute Rag1(-/-) mice. Furthermore, nCD4s deficient in IKK? also failed to reconstitute Rag1(-/-) mice and were defective in proliferative responses in vitro and in vivo. Thus, our study reveals a novel role of IKK? in the maintenance of a normal Treg population and in the control of expansion of CD4 T cells. These properties of IKK? may be exploited as therapeutic strategies in the treatment of major human diseases.-Chen, X., Willette-Brown, J.,Wu, X., Hu, Y., Howard, O. M. Z., Hu, Y., Oppenheim, J. J. IKK? is required for the homeostasis of regulatory T cells and for the expansion of both regulatory and effectorCD4 T cells.
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Insulin-Like Growth Factor-1 and Insulin-Like Growth Factor-Binding Protein-3 Concentrations in Children With Obstructive Sleep Apnea-Hypopnea Syndrome.
Respir Care
PUBLISHED: 11-06-2014
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The aim of this study was to assess insulin-like growth factor-1 (IGF-1) and insulin-like growth factor-binding protein-3 (IGFBP-3) concentrations in children with obstructive sleep apnea-hypopnea syndrome (OSAHS) and to compare the results according to disease severity and duration.
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[Expression and localization of the nuclear factor-?B classical signaling pathway in the radial artery of diabetic patients].
Zhonghua Wai Ke Za Zhi
PUBLISHED: 11-06-2014
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To observe the expression and localization of the nuclear factor-?B (NF-?B) classic signaling pathway in the radial artery of the coronary artery bypass grafting (CABG) patients with diabetes and non-diabetes.
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Theoretical Studies of Structure and Dynamics of Molten Salts: The LiF-ThF4 System.
J Phys Chem B
PUBLISHED: 11-01-2014
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LiF-ThF4 molten salt (MS) is the fuel in advanced molten salt reactors. Knowledge of the microscopic MS structure and dynamics is required for an understanding of the macroscopic physical and chemical properties of the MS phases. We have performed molecular dynamics simulations on LiF-ThF4 MSs at different compositions (LiF:ThF4 = 20 to 0.5) and temperatures (1100 to 1400 K). Experimental deductions and recent theoretical results on coordination structures and transport properties of the MSs are well reproduced. The density of states of the [ThF8]4- species and the character of the Th-F bonding are investigated. The interplay between the microscopic structures and the dynamical properties is elucidated. The activation barrier of the M4+-F- dissociation and the lifetime of the first coordination shell of M4+ are both smaller in the respective LiF-MF4 systems for M = Th than for M = Zr. The shorter Zr-F bond is stronger than the longer Th-F bond, while the coordination number of the predominant [ZrF7]3- species is smaller than that of the dominant [ThF8]4- species. An approximate formula is proposed for the lifetime of F- ions in the first solvation shell of molten MFn (M = Y, Zr, Th) in terms of the radial distribution function.
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Protein biomineralized nanoporous inorganic mesocrystals with tunable hierarchical nanostructures.
J. Am. Chem. Soc.
PUBLISHED: 10-27-2014
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Mesocrystals with the symmetry defying morphologies and highly ordered superstructures composed of primary units are of particular interest, but the fabrication has proved extremely challenging. A novel strategy based on biomineralization approach for the synthesis of hematite mesocrystals is developed by using silk fibroin as a biotemplate. The resultant hematite mesocrystals are uniform, highly crystalline, and porous nanostructures with tunable size and morphologies by simply varying the concentration of the silk fibroin and iron(III) chloride in this biomineralization system. In particular, we demonstrate a complex mesoscale biomineralization process induced by the silk fibroin for the formation of hematite mesocrystals. This biomimetic strategy features precisely tunable, high efficiency, and low-cost and opens up an avenue to access new novel functional mesocrystals with hierarchical structures in various practical applications.
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8q24 rs4242382 Polymorphism is a Risk Factor for Prostate Cancer among Multi-Ethnic Populations: Evidence from Clinical Detection in China and a Meta-analysis.
Asian Pac. J. Cancer Prev.
PUBLISHED: 10-24-2014
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Evidence supporting an association between the 8q24 rs4242382-A polymorphism and prostate cancer (PCa) risk has been reported in North American and Europe populations, though data from Asian populations remain limited. We therefore investigated this association by clinical detection in China, and meta-analysis in Asian, Caucasian and African-American populations.
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Breast cancer risk analysis based on a novel segmentation framework for digital mammograms.
Med Image Comput Comput Assist Interv
PUBLISHED: 10-22-2014
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The radiographic appearance of breast tissue has been established as a strong risk factor for breast cancer. Here we present a complete machine learning framework for automatic estimation of mammographic density (MD) and robust feature extraction for breast cancer risk analysis. Our framework is able to simultaneously classify the breast region, fatty tissue, pectoral muscle, glandular tissue and nipple region. Integral to our method is the extraction of measures of breast density (as the fraction of the breast area occupied by glandular tissue) and mammographic pattern. A novel aspect of the segmentation framework is that a probability map associated with the label mask is provided, which indicates the level of confidence of each pixel being classified as the current label. The Pearson correlation coefficient between the estimated MD value and the ground truth is 0.8012 (p-value < 0.0001). We demonstrate the capability of our methods to discriminate between women with and without cancer by analyzing the contralateral mammograms of 50 women with unilateral breast cancer, and 50 controls. Using MD we obtained an area under the ROC curve (AUC) of 0.61; however our texture-based measure of mammographic pattern significantly outperforms the MD discrimination with an AUC of 0.70.
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Disrupting the balance between tumor epithelia and stroma is a possible therapeutic approach for pancreatic cancer.
Med. Sci. Monit.
PUBLISHED: 10-21-2014
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Pancreatic ductal adenocarcinoma (PDAC) is a type of highly lethal malignant tumor. PDAC is locally invasive and is surrounded by a dense desmoplasia or fibrosis, which can involve adjacent vital structures. Previously, the effect of pancreatic stellate cells (PSCs) of stroma in the progression of PDAC has received more attention, and most in vitro and in vivo studies revealed that PSCs appear to confer biological aggressiveness. However, clinical trials targeting desmoplasia or PSCs showed disappointing results. Recent studies found that stromal components, especially activated PSCs, are able to inhibit the occurrence and progression of PDAC. Inhibition of the stroma or desmoplasia through genetic regulations or drugs accelerates the formation and progression of PDAC. Thus, we hypothesized that in various times and spaces, there is a balance between the tumor epithelia and stroma; once the balance is upset, the tumor traits may undergo certain changes. Therefore, finding the key changing points of this relationship to corrupt or influence it, instead of blindly inhibiting the stroma motivation or simply maintaining stroma activation, will destroy the cooperation or promote the competition and antagonism among cells. This approach may render tumors more vulnerable and thus unable to resist anti-cancer therapies.
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Ordered arrays of a defect-modified ferroelectric polymer for non-volatile memory with minimized energy consumption.
Nanoscale
PUBLISHED: 10-16-2014
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Ferroelectric polymers are among the most promising materials for flexible electronic devices. Highly ordered arrays of the defect-modified ferroelectric polymer P(VDF-TrFE-CFE) (poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene)) are fabricated by nanoimprint lithography for nonvolatile memory application. The defective CFE units reduce the coercive field to one-fifth of that of the un-modified P(VDF-TrFE), which can help minimize the energy consumption and extend the lifespan of the device. The nanoimprint process leads to preferable orientation of polymer chains and delicately controlled distribution of the defects, and thus a bi-stable polarization that makes the memory nonvolatile, as revealed by the pulsed polarization experiment.
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Isolation and Multiple Differentiation Potential Assessment of Human Gingival Mesenchymal Stem Cells.
Int J Mol Sci
PUBLISHED: 10-04-2014
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The aim of this study was to isolate human mesenchymal stem cells (MSCs) from the gingiva (GMSCs) and confirm their multiple differentiation potentials, including the odontogenic lineage. GMSCs, periodontal ligament stem cells (PDLSCs) and dermal stem cells (DSCs) cultures were analyzed for cell shape, cell cycle, colony-forming unit-fibroblast (CFU-F) and stem cell markers. Cells were then induced for osteogenic and adipogenic differentiation and analyzed for differentiation markers (alkaline phosphatase (ALP) activity, mineralization nodule formation and Runx2, ALP, osteocalcin (OCN) and collagen I expressions for the osteogenic differentiation, and lipid vacuole formation and PPAR?-2 expression for the adipogenic differentiation). Besides, the odontogenic differentiation potential of GMSCs induced with embryonic tooth germ cell-conditioned medium (ETGC-CM) was observed. GMSCs, PDLSCs and DSCs were all stromal origin. PDLSCs showed much higher osteogenic differentiation ability but lower adipogenic differentiation potential than DSCs. GMSCs showed the medial osteogenic and adipogenic differentiation potentials between those of PDLSCs and DSCs. GMSCs were capable of expressing the odontogenic genes after ETGC-CM induction. This study provides evidence that GMSCs can be used in tissue engineering/regeneration protocols as an approachable stem cell source.
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[Successful pregnancy following repeated implantation failure in patients with polycystic ovary syndrome: report of three cases].
Nan Fang Yi Ke Da Xue Xue Bao
PUBLISHED: 09-30-2014
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We report 3 cases of polycystic ovary syndrome (PCOS) in which the patients had successful pregnancy after repeated implantation failure in at least 8 in vitro fertilization and embryo transfer (IVF-ET) cycles. The patients were treated with gonadotropin-releasing hormone antagonist (GnRH-ant) protocol and gonadotropin-releasing hormone angonist (GnRHa) for triggering ovulation, and successful pregnancy and normal deliveries were achieved after 9 IVT-ET cycles. For young patients with PCOS but a good ovarian reserve and a high ovarian response, treatment with GnRH antagonist protocol and GnRHa alone with appropriate management of the factors that may affect implantation can prevent severe ovarian hyperstimulation syndrome to achieve favorable clinical outcomes.
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Tfh cell differentiation and their function in promoting B-cell responses.
Adv. Exp. Med. Biol.
PUBLISHED: 09-28-2014
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Follicular helper T cells (Tfh) are a newly defined helper T-cell subset that is specialized in facilitating B-cell responses. These cells have a unique tissue localization pattern and a distinct transcriptional program suited for the B-cell helper function. Co-opting of the follicular program affords regulatory T cells, NK T cells, and ?? T cells with opportunities to participate in the regulation of humoral immunity. Abnormal Tfh development and function can lead to immunodeficiencies, autoimmune inflammation, and tumors. Detailed understanding of Tfh cell differentiation and function in animal models and the human system promises better strategies toward vaccine development and therapies for inflammatory diseases.
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Investigation of alanine mutations affecting insulin-like growth factor (IGF) I binding to IGF binding proteins.
Growth Factors
PUBLISHED: 09-27-2014
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Abstract Binding properties of wild type (WT) and six single amino acid substituted variants (E3A, E9A, D12A, D20A, F23A, and E58A) of insulin-like growth factor I (IGF-I) were analyzed with respect to their binding details to IGF binding proteins (IGFBPs) by molecular dynamics (MD) simulations. The binding sites and binding interactions on IGF-I and IGFBPs are screened and compared with the static X-ray structure. Electrostatic interaction is the primary driving force of the interaction between IGF-I and IGFBPs. Mutation may cause the rearrangement of binding sites, however, the unfolding of protein induced by mutation is not obvious in this work. We also provide the detailed picture of binding factors. And the results show that, whether the unfolding of helix occurs or not, the Ala mutation will change the molecular atmosphere of the binding interface by the rearrangement of conformation, and further affects the binding residues and binding interactions.
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Differential effects of targeting Notch receptors in a mouse model of liver cancer.
Hepatology
PUBLISHED: 09-26-2014
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Primary liver cancer encompasses both hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC). The Notch signaling pathway, known to be important for the proper development of liver architecture, is also a potential driver of primary liver cancer. However, with four known Notch receptors and several Notch ligands, it is not clear which Notch pathway members play the predominant role in liver cancer. To address this question we utilized antibodies to specifically target Notch1, Notch2, Notch3 or Jag1 in a mouse model of primary liver cancer driven by AKT and NRas. We show that inhibition of Notch2 reduces tumor burden by eliminating highly malignant hepatocellular carcinoma- and cholangiocarcinoma-like tumors. Inhibition of the Notch ligand Jag 1 had a similar effect, consistent with Jag1 acting in cooperation with Notch2. This effect was specific to Notch2, as Notch3 inhibition did not decrease tumor burden. Unexpectedly, Notch1 inhibition altered the relative proportion of tumor types, reducing HCC-like tumors but dramatically increasing CC-like tumors. Finally, we show that Notch2 and Jag1 are expressed in, and Notch2 signaling is activated in, a subset of human HCC samples. Conclusions: These findings underscore the distinct roles of different Notch receptors in the liver and suggest that inhibition of Notch2 signaling represents a novel therapeutic option in the treatment of liver cancer. (Hepatology 2014;).
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[Effects of Annexin A2 gene transcription down-regulation on human hepatoma cell biological behaviour].
Zhonghua Gan Zang Bing Za Zhi
PUBLISHED: 09-23-2014
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To investigate the effects of Annexin A2 (ANXA2) deficiency on the malignant biological behaviour of hepatoma cells.
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Adaptive fuzzy output-feedback controller design for nonlinear systems via backstepping and small-gain approach.
IEEE Trans Cybern
PUBLISHED: 09-16-2014
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This paper focuses on an input-to-state practical stability (ISpS) problem of nonlinear systems which possess unmodeled dynamics in the presence of unstructured uncertainties and dynamic disturbances. The dynamic disturbances depend on the states and the measured output of the system, and its assumption conditions are relaxed compared with the common restrictions. Based on an input-driven filter, fuzzy logic systems are directly used to approximate the unknown and desired control signals instead of the unknown nonlinear functions, and an integrated backstepping technique is used to design an adaptive output-feedback controller that ensures robustness with respect to unknown parameters and uncertain nonlinearities. This paper, by applying the ISpS theory and the generalized small-gain approach, shows that the proposed adaptive fuzzy controller guarantees the closed-loop system being semi-globally uniformly ultimately bounded. A main advantage of the proposed controller is that it contains only three adaptive parameters that need to be updated online, no matter how many states there are in the systems. Finally, the effectiveness of the proposed approach is illustrated by two simulation examples.
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Neural mechanisms of coarse-to-fine discrimination in the visual cortex.
J. Neurophysiol.
PUBLISHED: 09-12-2014
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Vision is a dynamic process that refines the spatial scale of analysis over time, as evidenced by a progressive improvement in the ability to detect and discriminate finer details. To understand coarse-to-fine discrimination, we studied the dynamics of spatial frequency (SF) response using reverse correlation in the primary visual cortex (V1) of the primate. In a majority of V1 cells studied, preferred SF either increased monotonically with time (Group 1) or changed nonmonotonically, with an initial increase followed by a decrease (Group 2). Monotonic shift in preferred SF occurred with or without an early suppression at low SFs. Late suppression at high SFs always accompanied nonmonotonic SF dynamics. Bayesian analysis showed that SF discrimination performance and best discriminable SF frequencies changed with time in different ways in the two groups of neurons. In Group 1 neurons, SF discrimination performance peaked on both left and right flanks of the SF tuning curve at about the same time. In Group 2 neurons, peak discrimination occurred on the right flank (high SFs) later than on the left flank (low SFs). Group 2 neurons were also better discriminators of high SFs. We examined the relationship between the time at which SF discrimination performance peaked on either flank of the SF tuning curve and the corresponding best discriminable SFs in both neuronal groups. This analysis showed that the population best discriminable SF increased with time in V1. These results suggest neural mechanisms for coarse-to-fine discrimination behavior and that this process originates in V1 or earlier.
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[Screening for Lynch syndrome in colorectal cancer].
Zhonghua Bing Li Xue Za Zhi
PUBLISHED: 09-12-2014
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To evaluate the application of mismatch repair (MMR) genes proteins expression to screen for Lynch syndrome in colorectal cancer patients.
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The Alarmin HMGN1 Contributes to Antitumor Immunity and Is a Potent Immunoadjuvant.
Cancer Res.
PUBLISHED: 09-09-2014
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Alarmins are endogenous mediators that are elicited rapidly in response to danger signals, enhancing innate and adaptive immune responses by promoting the recruitment and maturation of antigen-presenting cells (APC). The nucleosome-binding protein HMGN1 is a potent alarmin that binds TLR4 and induces antigen-specific Th1 immune responses, but its contributions to antitumor immunity have not been explored. We found that ovalbumin (OVA)-expressing EG7 mouse thymoma cells grew much faster in Hmgn1-deficient mice than littermate-matched controls. Tumor-bearing Hmgn1(-/-) mice generated fewer OVA-specific CD8 cells in the spleen than EG7-bearing Hmgn1(+/+) mice, suggesting that HMGN1 supported T cell-mediated antitumor immunity. In addition, EG7 tumors expressing HMGN1 grew more slowly than control EG7 tumors, suggesting greater resistance to HMGN1-expressing tumors. This resistance relied on T cell-mediated immunity because it was abolished by in vivo depletion of CD4(+) and CD8(+) T cells. Moreover, mice vaccinated with a DNA vector expressing an HMGN1-gp100 fusion protein manifested gp100-specific, Th1-polarized immune responses, acquiring resistance to challenge with mouse B16F1 melanoma. Overall, our findings show that HMGN1 contributes to antitumor immunity and it may offer an effective adjuvant to heighten responses to cancer vaccines. Cancer Res; 74(21); 5989-98. ©2014 AACR.
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Anti-rheumatic agent auranofin induced apoptosis in chronic myeloid leukemia cells resistant to imatinib through both Bcr/Abl-dependent and -independent mechanisms.
Oncotarget
PUBLISHED: 09-07-2014
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Resistance to Imatinib mesylate (IM) is an emerging problem for patients with chronic myelogenous leukemia (CML). T315I mutation in the Bcr-Abl is the predominant mechanism of the acquired resistance to IM and second generation tyrosine kinase inhibitors (TKI). Therefore it is urgent to search for new measures to overcome TKI-resistance. Auranofin (AF), clinically used to treat rheumatic arthritis, was recently approved by US Food and Drug Administration for Phase II clinical trial to treat cancer. In contrast to the reports that AF induces apoptosis by increasing intracellular reactive oxygen species (ROS) levels via inhibiting thioredoxin reductase, our recent study revealed that AF-induced apoptosis depends on inhibition of proteasomal deubiquitinases (UCHL5 and USP14). Here we report that (i) AF induces apoptosis in both Bcr-Abl wild-type cells and Bcr-Abl-T315I mutation cells and inhibits the growth of IM-resistant Bcr-Abl-T315I xenografts in vivo; (ii) AF inhibits Bcr-Abl through both downregulation of Bcr-Abl gene expression and Bcr-Abl cleavage mediated by proteasome inhibition-induced caspase activation; (iii) proteasome inhibition but not ROS is required for AF-induced caspase activation and apoptosis. These findings support that AF overcomes IM resistance through both Bcr/Abl-dependent and -independent mechanisms, providing great clinical significance for cancer treatment.
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A new method for synthesis of peptide thioesters via irreversible N-to-S acyl transfer.
Org. Lett.
PUBLISHED: 09-04-2014
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A new synthetic method for peptide thioesters is described using Fmoc solid-phase peptide synthesis (Fmoc-SPPS). This method employs a novel enamide motif to facilitate irreversible intramolecular N-to-S acyl migration, which can efficiently afford the desired peptide thioesters (3 h, 30 °C) under the final trifluoroacetic acid (TFA) cleavage conditions. The acyl-transfer-mediated approach for synthesis of peptide thioesters tolerated different C-terminal residues and was used to synthesize human C-C motif chemokine 11 (hCCL11) via native chemical ligation.
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A Three-Dimensional Microdisplacement Sensing System Based on MEMS Bulk-Silicon Technology.
Sensors (Basel)
PUBLISHED: 08-28-2014
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For the dimensional measurement and characterization of microsized and nanosized components, a three-dimensional microdisplacement sensing system was developed using the piezoresistive effect in silicon. The sensor was fabricated using microelectromechanical system bulk-silicon technology, and it was validated using the finite element method. A precise data acquisition circuit with an accuracy of 20 ?V was designed to obtain weak voltage signals. By calibration, the sensing system was shown to have a sensitivity of 17.29 mV/?m and 4.59 mV/?m in the axial and lateral directions, respectively; the nonlinearity in these directions was 0.8% and 1.0% full scale, respectively. A full range of 4.6 ?m was achieved in the axial direction. Results of a resolution test indicated that the sensing system had a resolution of 5 nm in the axial direction and 10 nm in the lateral direction.
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miR-372 regulates glioma cell proliferation and invasion by directly targeting PHLPP2.
J. Cell. Biochem.
PUBLISHED: 08-27-2014
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MicroRNAs are known to be involved in carcinogenesis and tumor progression in glioma. Recently, microRNA-372 (miR-372) has been proved to play a substantial role in several human cancers, but its functions in glioma remain unclear. In this study, we confirmed that miR-372 was commonly upregulated in glioma cell lines and tissues. Downregulation of miR-372 markedly inhibited cell proliferation and invasion and induced G1/S arrest and apoptosis. Consistently, the xenograft mouse model also unveiled the suppressive effects of miR-372 knockdown on tumor growth. Further studies revealed that miR-372 modulated the expression of PHLPP2 by directly targeting its 3'-untranslated region (3'-UTR) and that miR-372 expression was inversely correlated with PHLPP2 expression in glioma samples. Silencing of PHLPP2 could rescue the inhibitory effect of miR-372 inhibitor. Moreover, miR-372 knockdown suppressed the phosphorylation levels of the major components of PI3K/Akt pathway including Akt, mTOR and P70S6K. Taken together, our results suggest that miR-372 functions as an oncogenic miRNA through targeting PHLPP2 in glioma. J. Cell. Biochem. © 2014 Wiley Periodicals, Inc.
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Large area and depth-profiling dislocation imaging and strain analysis in Si/SiGe/Si heterostructures.
Microsc. Microanal.
PUBLISHED: 08-27-2014
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We demonstrate the combined use of large area depth-profiling dislocation imaging and quantitative composition and strain measurement for a strained Si/SiGe/Si sample based on nondestructive techniques of electron beam-induced current (EBIC) and X-ray diffraction reciprocal space mapping (XRD RSM). Depth and improved spatial resolution is achieved for dislocation imaging in EBIC by using different electron beam energies at a low temperature of ~7 K. Images recorded clearly show dislocations distributed in three regions of the sample: deep dislocation networks concentrated in the "strained" SiGe region, shallow misfit dislocations at the top Si/SiGe interface, and threading dislocations connecting the two regions. Dislocation densities at the top of the sample can be measured directly from the EBIC results. XRD RSM reveals separated peaks, allowing a quantitative measurement of composition and strain corresponding to different layers of different composition ratios. High-resolution scanning transmission electron microscopy cross-section analysis clearly shows the individual composition layers and the dislocation lines in the layers, which supports the EBIC and XRD RSM results.
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Diverse forms of HIV-1 among Burmese long-distance truck drivers imply their contribution to HIV-1 cross-border transmission.
BMC Infect. Dis.
PUBLISHED: 08-26-2014
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The China-Myanmar border is a particularly interesting region that has very high prevalence of and considerable diversity of HIV-1 recombinants. Due to the transient nature of their work, long-distance truck drivers (LDTDs) have a comparatively high potential to become infected with HIV-1 and further spread virus to other individuals in the area they travel within. In this study, we hypothesized that Burmese LDTDs crossing the China-Myanmar border frequently may potentially be involved in the cross-border transmission of HIV, and contribute to the extremely high prevalence of HIV-1 inter-subtype recombinants in this border region.
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Characterization and profiling of phenolic amides from Cortex Lycii by ultra-high performance liquid chromatography coupled with LTQ-Orbitrap mass spectrometry.
Anal Bioanal Chem
PUBLISHED: 08-25-2014
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Cortex Lycii, the root bark of Lycium chinense Mill. or Lycium barbarum L., is a frequently used traditional Chinese medicine. Phytochemical studies have shown that phenolic amides are not only characteristic compounds but also abundant ones in this plant. In the present study, an effective method was developed for structural characterization of phenolic amides from Cortex Lycii by ultra-high performance liquid chromatography coupled with linear ion trap Orbitrap tandem mass spectrometry. The fragmentation of 14 compounds including six cinnamic acid amides, six neolignanamides, and two lignanamides were studied systematically for the first time. It was found that, in the positive ion mode, neutral loss of the tyramide moiety (137 Da) or N-(4-aminobutyl)acetamide moiety (130 Da) were characteristic for these compounds. At least 54 phenolic amides were detected in the extract and 48 of them were characterized, among which 14 known compounds were identified unambiguously by comparing the retention time and mass spectra with those of reference compounds, and 34 components were tentatively identified based on the fragmentation patterns, exact mass, UV spectra, as well as retention time. Fifteen compounds were characterized as potential new ones. Additionally, the developed method was applied to analyze eight batches of samples collected from the northwest of China, and it was found that cinnamic acid amides were the main type of phenolic amides in Cortex Lycii. In conclusion, the identification of these chemicals provided essential data for further phytochemical studies, metabolites identification, and the quality control of Cortex Lycii.
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Arylacetylene-Substituted Naphthalene Diimides with Dual Functions: Optical Waveguides and n-Type Semiconductors.
Chem Asian J
PUBLISHED: 08-25-2014
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New arylacetylene-substituted naphthalene diimides (NDIs) 1-6, with both light-emitting and semiconducting functions, are reported. Among them, the crystal structure of 1 was determined. On the basis of their reduction potentials and thin-film absorption spectra, the HOMO/LUMO energies of these modified NDIs were estimated. The results reveal that their HOMO/LUMO energies are slightly affected by the flanking aryl groups. The emission colors of these NDIs vary from green to red, and interestingly, they show aggregation-induced emission enhancement behavior with fluorescence quantum yields reaching 9.86?% in the solid state. Microrods of 1, 3, and 5 show typical optical wave-guiding behavior with relatively low optical-loss coefficients. Organic field-effect transistors with thin films of these NDIs were fabricated with conventional techniques. The results indicate that thin films of 2, 4, and 6, with long and branched alkyl chains, show air-stable n-type semiconducting properties with electron mobilities of up to 0.035?cm(2) ?V(-1) ?s(-1) after thermal annealing, whereas 1, 3, and 5, with short alkyl chains, behave as n-type semiconductors under a nitrogen atmosphere with electron mobilities of up to 0.075?cm(2) ?V(-1) ?s(-1) after thermal annealing.
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Biocompatible Reactive Oxygen Species (ROS)-Responsive Nanoparticles as Superior Drug Delivery Vehicles.
Adv Healthc Mater
PUBLISHED: 08-22-2014
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A novel reactive oxygen species (ROS)-responsive nanoplatform can be successfully manufactured from a ROS-triggerable ?-cyclodextrin material. Extensive in vitro and in vivo studies validate that this nanoscaled system may serve as a new drug delivery vehicle with well-defined ROS-sensitivity and superior biocompatibility. This nanocarrier can be used for ROS-triggered transport of diverse therapeutics and imaging agents.
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4EBP1/eIF4E and p70S6K/RPS6 axes play critical and distinct roles in hepatocarcinogenesis driven by AKT and N-Ras protooncogenes.
Hepatology
PUBLISHED: 08-22-2014
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Concomitant expression of activated forms of AKT and Ras in the mouse liver (AKT/Ras) leads to rapid tumor development via strong activation of the mTORC1 pathway. mTORC1 functions via regulating p70S6K/RPS6 and 4EBP1/eIF4E cascades. How these cascades contribute to hepatocarcinogenesis remains unknown. Here, we show that inhibition of RPS6 pathway via Rapamycin effectively suppressed, whereas blockade of the 4EBP1/eIF4E cascade by 4EBP1A4, an unphosphorylatable form of 4EBP1, significantly delayed, AKT/Ras induced hepatocarcinogenesis. Combined treatment with Rapamycin and 4EBP1A4 completely inhibited AKT/Ras hepatocarcinogenesis. This strong anti-neoplastic effect was successfully recapitulated by ablating Raptor, the major subunit of mTORC1, in AKT/Ras-overexpressing livers. Furthermore, we demonstrate that overexpression of eIF4E, the protooncogene whose activity is specifically inhibited by 4EBP1, resulted in HCC development in cooperation with activated Ras. Mechanistically, we identified the ENTPD5/AK1/CMPK1 axis and the mitochondrial biogenesis pathway as targets of the 4EBP1/eIF4E cascade in AKT/Ras and Ras/eIF4E livers as well as in human HCC cell lines and tissues. Conclusions: Complete inhibition of mTORC1 is required to suppress liver cancer development induced by AKT and Ras protooncogenes in mice. The mTORC1 effectors, RPS6 and eIF4E, play distinct roles and are both necessary for AKT/Ras hepatocarcinogenesis. These new findings might open the way for innovative therapies against human hepatocellular carcinoma. (Hepatology 2014).
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[Effect of acupuncture-anesthetic composite anesthesia on the incidence of POCD and TNF-alpha, IL-1beta, IL-6 in elderly patients].
Zhongguo Zhong Xi Yi Jie He Za Zhi
PUBLISHED: 08-21-2014
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To explore the effect of acupuncture-anesthetic composite anesthesia (AACA) on the incidence of postoperative cognitive dysfunction (POCD) and changes of TNF-alpha, IL-1beta, and IL-6 in elderly patients.
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The impacts of obstructive sleep apnea hypopnea syndrome severity and surgery intervention on psychological and behavioral abnormalities and postoperative recovery in pediatric patients.
Med. Sci. Monit.
PUBLISHED: 08-19-2014
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The aim of this study was to investigate the degree of impact of obstructive sleep apnea hypopnea syndrome (OSAHS) severity on pediatric psychological and behavioral abnormalities.
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Protoplast fusion enhances lignocellulolytic enzyme activities in Trichoderma reesei.
Biotechnol. Lett.
PUBLISHED: 08-19-2014
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Protoplast fusion was used to obtain a higher production of lignocellulolytic enzymes with protoplast fusion in Trichoderma reesei. The fusant strain T. reesei JL6 was obtained from protoplast fusion from T. reesei strains QM9414, MCG77, and Rut C-30. Filter paper activity of T. reesei JL6 increased by 18 % compared with that of Rut C-30. ?-Glucosidase, hemicellulase and pectinase activities of T. reesei JL6 were also higher. The former activity was 0.39 Uml(-1), while those of QM9414, MCG77, and Rut C-30 were 0.13, 0.11, and 0.16 Uml(-1), respectively. Pectinase and hemicellulase activities of JL6 were 5.4 and 15.6 Uml(-1), respectively, which were slightly higher than those of the parents. The effects of corn stover and wheat bran carbon sources on the cellulase production and growth curve of T. reesei JL6 were also investigated.
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Trophectoderm morphology predicts outcomes of pregnancy in vitrified-warmed single-blastocyst transfer cycle in a Chinese population.
J. Assist. Reprod. Genet.
PUBLISHED: 08-16-2014
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In this study, we estimated the effect of blastocoele expansion, ICM and TE quality after warming and culture on the rates of clinical pregnancy, live birth and miscarriage in vitrified-warmed single-blastocyst transfer cycle in a Chinese population.
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Myosin Light Chain Kinase (MLCK) Regulates Cell Migration in a Myosin Regulatory Light Chain Phosphorylation-independent Mechanism.
J. Biol. Chem.
PUBLISHED: 08-13-2014
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Myosin light chain kinase (MLCK) has long been implicated in the myosin phosphorylation and force generation required for cell migration. Here, we surprisingly found that the deletion of MLCK resulted in fast cell migration, enhanced protrusion formation, and no alteration of myosin light chain phosphorylation. The mutant cells showed reduced membrane tether force and fewer membrane F-actin filaments. This phenotype was rescued by either kinase-dead MLCK or five-DFRXXL motif, a MLCK fragment with potent F-actin-binding activity. Pull-down and co-immunoprecipitation assays showed that the absence of MLCK led to attenuated formation of transmembrane complexes, including myosin II, integrins and fibronectin. We suggest that MLCK is not required for myosin phosphorylation in a migrating cell. A critical role of MLCK in cell migration involves regulating the cell membrane tension and protrusion necessary for migration, thereby stabilizing the membrane skeleton through F-actin-binding activity. This finding sheds light on a novel regulatory mechanism of protrusion during cell migration.
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Saccharomyces cerevisiae Sen1 as a Model for the Study of Mutations in Human Senataxin That Elicit Cerebellar Ataxia.
Genetics
PUBLISHED: 08-12-2014
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The nuclear RNA and DNA helicase Sen1 is essential in the yeast Saccharomyces cerevisiae and is required for efficient termination of RNA polymerase II transcription of many short noncoding RNA genes. However, the mechanism of Sen1 function is not understood. We created a plasmid-based genetic system to study yeast Sen1 in vivo. Using this system, we show that (1) the minimal essential region of Sen1 corresponds to the helicase domain and one of two flanking nuclear localization sequences; (2) a previously isolated terminator readthrough mutation in the Sen1 helicase domain, E1597K, is rescued by a second mutation designed to restore a salt bridge within the first RecA domain; and (3) the human ortholog of yeast Sen1, Senataxin, cannot functionally replace Sen1 in yeast. Guided by sequence homology between the conserved helicase domains of Sen1 and Senataxin, we tested the effects of 13 missense mutations that cosegregate with the inherited disorder ataxia with oculomotor apraxia type 2 on Sen1 function. Ten of the disease mutations resulted in transcription readthrough of at least one of three Sen1-dependent termination elements tested. Our genetic system will facilitate the further investigation of structure-function relationships in yeast Sen1 and its orthologs.
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Doxorubicin-loaded magnetic silk fibroin nanoparticles for targeted therapy of multidrug-resistant cancer.
Adv. Mater. Weinheim
PUBLISHED: 08-05-2014
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A strategy to prepare doxorubicin-loaded magnetic silk fibroin nanoparticles is presented. The nanoparticles serve as a nanometer-scale drug-delivery system in the chemotherapy of multidrug-resistant cancer under the guidance of a magnetic field. The magnetic tumor-targeting ability broadens the range of biomedical applications of silk fibroin, and the nanoparticle-assisted preparation strategy is useful for the advancement of other biomacromolecule-based materials.
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miR-21 improves the neurological outcome after traumatic brain injury in rats.
Sci Rep
PUBLISHED: 07-10-2014
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The expression levels of microRNAs (miRNAs) including miR-21, have been reported to change in response to traumatic brain injury (TBI), suggesting that they may influence the pathophysiological process in brain injury. To analyze the potential effect of miR-21 on neurological function after TBI, we employed the fluid percussion injury rat model and manipulated the expression level of miR-21 in brain using intracerebroventricular infusion of miR-21 agomir or antagomir. We found that upregulation of miR-21 level in brain conferred a better neurological outcome after TBI by improving long-term neurological function, alleviating brain edema and decreasing lesion volume. To further investigate the mechanism underlying this protective effect, we evaluated the impact of miR-21 on apoptosis and angiogenesis in brain after TBI. We found that miR-21 inhibited apoptosis and promoted angiogenesis through regulating the expression of apoptosis- and angiogenesis-related molecules. In addition, the expression of PTEN, a miR-21 target gene, was inhibited and Akt signaling was activated in the procedure. Taken together, these data indicate that miR-21 could be a potential therapeutic target for interventions after TBI.
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Molecular chaperones (TrxA, SUMO, Intein and GST) Mediating Expression, Purification and Antimicrobial Activity Assays of Plectasin in Escherichia coli.
Biotechnol. Appl. Biochem.
PUBLISHED: 07-08-2014
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Plectasin is the first defensin to be isolated from a fungus, the saprophytic ascomycete Pseudoplectania nigrella, and active against Streptococcus pneumonia and S. aureus, including antibiotic-resistant pathogens. In order to establish a bacterium-based production system, we compared the efficiency of four molecular chaperones and corresponding cleavage to the expression and purification of plectasin. The results showed that the yield of plectasin combined with Thioredoxin A (TrxA) and Small Ubiquitin-related modifier (SUMO) were at higher level (0.0356 g l(-1) , 0.0358 g l(-1) ) than that with Intein (0.0238 g l(-1) ) and Glutathione-S-transferase (GST) (0.0243 g l(-1) ). TrxA-Plectasin, SUMO-Plectasin and Intein2-Plectasin were cleaved at the correct site and purified, but considerable amount of them was not cleaved and remained as fusion peptide. The antimicrobial activity of plectasin cleaved from SUMO- Plectasin against Methicillin-resistant Staphylococcus aureus (MRSA), Penicillin-Resistant Streptococcus Pneumoniae (PRSP), Vancomycin-Resistant Enterococci (VRE) were stronger than Ampicillin (Amp) for the same amount of substance (P?0.05). This is the first study to complete and compare the effect of different molecular chaperones and corresponding cleavage with the expression and purification of plectasin in Escherichia Coli (E.coli) expression system, which laid the foundation for future research and may develop the application and production of plectasin. This article is protected by copyright. All rights reserved.
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Predictive factors associated with gefitinib response in patients with advanced non-small-cell lung cancer (NSCLC).
Chin. J. Cancer Res.
PUBLISHED: 07-02-2014
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A number of different clinical characteristics have been reported to singly correlate with therapeutic activity of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) in advanced non-small-cell lung cancer (NSCLC). This study aimed to identify predictive factors associated with prognostic benefits of gefitinib.
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Follicular fluid A?40 concentrations may be associated with ongoing pregnancy following in vitro fertilization.
J. Assist. Reprod. Genet.
PUBLISHED: 06-17-2014
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To determine whether A?40 levels in the follicular fluid (FF) of infertile women undergoing IVF demonstrate a relationship with IVF cycle parameters and outcome.
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Complete genome sequence of Thalassolituus oleivorans R6-15, an obligate hydrocarbonoclastic marine bacterium from the Arctic Ocean.
Stand Genomic Sci
PUBLISHED: 06-15-2014
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Strain R6-15 belongs to the genus Thalassolituus, in the family Oceanospirillaceae of Gammaproteobacteria. Representatives of this genus are known to be the obligate hydrocarbonoclastic marine bacteria. Thalassolituus oleivorans R6-15 is of special interest due to its dominance in the crude oil-degrading consortia enriched from the surface seawater of the Arctic Ocean. Here we describe the complete genome sequence and annotation of this strain, together with its phenotypic characteristics. The genome with size of 3,764,053 bp comprises one chromosome without any plasmids, and contains 3,372 protein-coding and 61 RNA genes, including 12 rRNA genes.
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A Comprehensive Transcriptome Provides Candidate Genes for Sex Determination/Differentiation and SSR/SNP Markers in Yellow Catfish.
Mar. Biotechnol.
PUBLISHED: 06-04-2014
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Sex dimorphic growth pattern has significant theory and application implications in fish. Recently, a Y- and X-specific allele marker-assisted sex control technique has been developed for mass production of all-male population in yellow catfish (Pelteobagrus fulvidraco), but the genetic information for sex determination and sex control breeding has remained unclear. Here, we attempted to provide the first insight into a comprehensive transcriptome covering multiple tissues from XX females, XY males, and YY super-males of yellow catfish by using 454 GS-FLX platform, for a better assembly and gene coverage. A total of 1,202,933 high quality reads (about 540 Mbp) were obtained and assembled into 28,297 contigs and 141,951 singletons. BLASTX searches against the NCBI non-redundant protein database (nr) led a total of 52,564 unique sequences including 18,748 contigs and 33,816 singletons to match 25,669 known or predicted unique proteins. All of them with annotated function were categorized by gene ontology (GO) analysis, and 712 were assigned to reproduction and reproductive process. Some potential genes relevant to reproductive system including steroid hormone biosynthesis and GnRH (gonadotropin-releasing hormone) signaling pathway were further identified by Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis; and at least 21 sex determination and differentiation-related genes, such as Dmrt1, Sox9a/b, Cyp19b, WT1, and AMH were identified and characterized. Additionally, a total of 82,794 simple sequence repeats (SSRs), 26,450 single nucleotide polymorphisms (SNPs), and 4,145 insertions and deletions (INDELs) were revealed from the transcriptome data. Therefore, the current transcriptome resources highlight further studies on sex-control breeding in yellow catfish and will benefit future studies on reproduction and sex determination in teleost fish.
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Understanding the commonalities and differences in genomic organizations across closely related bacteria from an energy perspective.
Sci China Life Sci
PUBLISHED: 05-25-2014
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The availability of a large number of sequenced bacterial genomes facilitates in-depth studies about why genes (operons) in a bacterial genome are globally organized the way they are. We have previously discovered that (the relative) transcription- activation frequencies among different biological pathways encoded in a genome have a dominating role in the global arrangement of operons. One complicating factor in such a study is that some operons may be involved in multiple pathways with different activation frequencies. A quantitative model has been developed that captures this information, which tends to be minimized by the current global arrangement of operons in a bacterial (and archaeal) genome compared to possible alternative arrangements. A study is carried out here using this model on a collection of 52 closely related E. coli genomes, which revealed interesting new insights about how bacterial genomes evolve to optimally adapt to their environments through adjusting the (relative) genomic locations of the encoding operons of biological pathways once their utilization and hence transcription activation frequencies change, to maintain the above energy-efficiency property. More specifically we observed that it is the frequencies of the transcription activation of pathways relative to those of the other encoded pathways in an organism as well as the variation in the activation frequencies of a specific pathway across the related genomes that play a key role in the observed commonalities and differences in the genomic organizations of genes (and operons) encoding specific pathways across different genomes.
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Pharmacokinetics of Sifuvirtide in Treatment-Naive and Treatment-Experienced HIV-Infected Patients.
J Pharm Sci
PUBLISHED: 04-07-2014
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The pharmacokinetics assessment in two clinical studies of sifuvirtide (a novel HIV fusion inhibitor) was first reported in Chinese HIV patients. Nineteen treatment-naive HIV patients were treated with s.c.(subcutaneous injection) sifuvirtide [10 or 20 mg q.d.(quaque die)] for 28 days in study 1, and eight treatment-experienced HIV patients were treated with s.c. sifuvirtide (20 mg q.d.) in combination with HAART drugs (lamivudine, didanosine, and Kaletra) for 168 days in study 2. In study 1, T1/2 was 17.8 ± 3.7 h for 10 mg group and 39.0 ± 3.5 h for 20 mg group; the mean Cmax of last dose was 498 ± 54 ng/mL for 10 mg group and 897 ± 136 ng/mL for 20 mg group. In study 2, T1/2 was 6.71 ± 2.17 h in treatment-experienced patients. Cmax was 765 ± 288 ng/mL after last 168th dosage. Sifuvirtide showed improved clinical pharmacokinetics characteristics compared with Enfuvirtide, and showed very different pharmacokinetic characteristics between treatment-naive and treatment-experienced patients. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 103:4038-4047, 2014.
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Chemokine receptor 4 gene silencing blocks neuroblastoma metastasis in vitro.
Neural Regen Res
PUBLISHED: 04-05-2014
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This study investigated the effects of small interfering RNA (siRNA)-mediated silencing of chemokine receptor 4 (CXCR4) on the invasion capacity of human neuroblastoma cell line SH-SY5Y in vitro. Three siRNAs targeting CXCR4 were chemically synthesized and individually transfected into SH-SY5Y cells. Expression of CXCR4 mRNA and protein was significantly suppressed in transfected cells by all three sequence-specific siRNAs compared with control groups. Furthermore, the invasion capacity of SH-SY5Y cells was significantly decreased following transfection with CXCR4-specific siRNA compared with the control groups. These data demonstrate that down-regulation of CXCR4 can inhibit in vitro invasion of neuroblastoma.
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Cassava genome from a wild ancestor to cultivated varieties.
Nat Commun
PUBLISHED: 03-20-2014
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Cassava is a major tropical food crop in the Euphorbiaceae family that has high carbohydrate production potential and adaptability to diverse environments. Here we present the draft genome sequences of a wild ancestor and a domesticated variety of cassava and comparative analyses with a partial inbred line. We identify 1,584 and 1,678 gene models specific to the wild and domesticated varieties, respectively, and discover high heterozygosity and millions of single-nucleotide variations. Our analyses reveal that genes involved in photosynthesis, starch accumulation and abiotic stresses have been positively selected, whereas those involved in cell wall biosynthesis and secondary metabolism, including cyanogenic glucoside formation, have been negatively selected in the cultivated varieties, reflecting the result of natural selection and domestication. Differences in microRNA genes and retrotransposon regulation could partly explain an increased carbon flux towards starch accumulation and reduced cyanogenic glucoside accumulation in domesticated cassava. These results may contribute to genetic improvement of cassava through better understanding of its biology.
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MRI quantification of non-Gaussian water diffusion in normal human kidney: a diffusional kurtosis imaging study.
NMR Biomed
PUBLISHED: 03-11-2014
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Our aim was to prospectively evaluate the feasibility of diffusional kurtosis imaging (DKI) in normal human kidney and to report preliminary DKI measurements. Institutional review board approval and informed consent were obtained. Forty-two healthy volunteers underwent diffusion-weighted imaging (DWI) scans with a 3-T MR scanner. b values of 0, 500 and 1000?s/mm(2) were adopted. Maps of fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (D? ), axial diffusivity (D|| ), mean kurtosis (MK), radial kurtosis (K? ) and axial kurtosis (K|| ) were produced. Three representative axial slices in the upper pole, mid-zone and lower pole were selected in the left and right kidney. On each selected slice, three regions of interest were drawn on the renal cortex and another three on the medulla. Statistical comparison was performed with t-test and analysis of variance. Thirty-seven volunteers successfully completed the scans. No statistically significant differences were observed between the left and right kidney for all metrics (p values in the cortex: FA, 0.114; MD, 0.531; D? , 0.576; D|| , 0.691; MK, 0.934; K? , 0.722; K|| , 0.891; p values in the medulla: FA, 0.348; MD, 0.732; D? , 0.470; D|| , 0.289; MK, 0.959; K? , 0.780; K|| , 0.287). Kurtosis metrics (MK, K|| , K? ) obtained in the renal medulla were significantly (p <0.001) higher than those in the cortex (0.552?±?0.04, 0.637?±?0.07 and 0.530?±?0.08 in the medulla and 0.373?±?0.04, 0.492?±?0.06 and 0.295?±?0.06 in the cortex, respectively). For the diffusivity measures, FA of the medulla (0.356?±?0.03) was higher than that of the cortex (0.179?±?0.03), whereas MD, D? and D|| (mm(2) /ms) were lower in the medulla than in the cortex (3.88?±?0.09, 3.50?±?0.23 and 4.65?±?0.29 in the cortex and 2.88?±?0.11, 2.32?±?0.20 and 3.47?±?0.31 in the medulla, respectively). Our results indicate that DKI is feasible in the human kidney. We have reported the preliminary DKI measurements of normal human kidney that demonstrate well the non-Gaussian behavior of water diffusion, especially in the renal medulla. Copyright © 2014 John Wiley & Sons, Ltd.
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Bond competition and phase evolution on the IrTe2 surface.
Nat Commun
PUBLISHED: 02-26-2014
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Compounds with incommensurate structural modulations have been extensively studied in last several decades. However, the relationship between structurally incommensurate/commensurate phases and associated electronic states remains enigmatic. Here we report the coexisting of complex incommensurate structures and highly unusual electronic roughness on the surface of in situ cleaved IrTe2 by using scanning tunnelling microscopy/spectroscopy, corroborated with extensive density-functional theory calculations. This behaviour is traced to structural instability, which induces a structural transition from a trigonal to a triclinic lattice below transition temperature, giving rise to the formation of unidirectional structural modulations with distinct wavelengths, accompanied by the opening of a 'pseudo'-gap in the surface layer. With further cooling the surface adopts a structure that reflects an ~6 × periodicity that is different from the bulk 5 × periodicity. Calculations show that the structure distortion is not associated with a charge density wave, but is rather associated with Te p-electron bonding.
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Baicalin suppresses iron accumulation after substantia nigra injury: relationship between iron concentration and transferrin expression.
Neural Regen Res
PUBLISHED: 02-26-2014
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Previous studies have shown that baicalin prevented iron accumulation after substantia nigra injury, reduced divalent metal transporter 1 expression, and increased ferroportin 1 expression in the substantia nigra of rotenone-induced Parkinson's disease rats. In the current study, we investigated the relationship between iron accumulation and transferrin expression in C6 cells, to explore the mechanisms of the inhibitory effect of baicalin on iron accumulation observed in Parkinson's disease rats. Iron content was detected using inductively coupled plasma-atomic emission spectroscopy. Results showed that iron content decreased 41% after blocking divalent metal transporter 1 and ferroportin 1 proteins. After treatment with ferric ammonium citrate of differing concentrations (10, 50, 100, 400?g/mL) in C6 glioma cells, cell survival rate and ferroportin 1 expression were negatively correlated with ferric ammonium citrate concentration, but divalent metal transporter 1 expression positively correlated with ferric ammonium citrate concentration. Baicalin or deferoxamine reduced divalent metal transporter 1 expression, but increased ferroportin 1 expression in the 100?g/mL ferric ammonium citrate-loaded C6 cells. These results indicate that baicalin down-regulated iron concentration, which positively regulated divalent metal transporter 1 expression and negatively regulated ferroportin 1 expression, and decreased iron accumulation in the substantia nigra.
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Utilizing water characteristics and sediment nitrogen isotopic features to identify non-point nitrogen pollution sources at watershed scale in Liaoning Province, China.
Environ Sci Pollut Res Int
PUBLISHED: 02-25-2014
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Identifying nitrogen (N) pollution sources is the fundamental work of non-point source pollution load reduction from watersheds, but is hard due to complex N transport and transformation within spatially heterogenized huge areas. During September 2011, we measured water characteristics and sediment N stable isotope in four tributaries of the upper reach of the Hun River, an important water source of the Dahuofang Reservoir, a large drinking water source in Northeast China. Results showed that spatial changes in SO4 (2-) and Cl(-) contents in the tributaries were consisted with the changes in density of the population living along the tributaries. Sediment ?(15)N from all tributaries showed a downstream increasing trend in line with the land use change, which is characterized as more farmlands and more people around the outlet area of each tributary. Principal component analysis indicated the population density had a strong impact on N in these tributaries in the low-flow period. Tributaries and villages close to the Dahuofang Reservoir should be the major N load control objects in reduction of non-point source nitrogen load from the upper reach of the Hun River.
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AEG-1 expression correlates with CD133 and PPP6c levels in human glioma tissues.
J Biomed Res
PUBLISHED: 02-08-2014
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Astrocyte elevated gene-1 (AEG-1) is associated with tumor genesis and progression in a variety of human cancers. This study aimed to explore the significance of AEG-1 in glioma and investigate whether it correlated with radioresistance of glioma cells. Immunohistochemical staining showed that the intensity of AEG-1, CD133 and PPP6c protein expression in glioma tissues increased significantly, mainly in the cytoplasm. The expression rate of AEG-1, CD133 and PPP6c were 85.9% (67/78), 60.3% (47/78) and 65.8% (51/78), respectively. AEG-1 expression was correlated with age (r?=?0.227, P?=?0.045), clinical stage (r?=?0.491, P<0.001) and clinical grade (r?=?0.450, P<0.001). No correlation was found between AEG-1 expression and other clinicopathologic parameters (P>0.05). The expression of AEG-1 was positively correlated with the expression of CD133 (r?=?0.240, P ?=? 0.035) and PPP6c (r?=? 0.250, P ?=? 0.027). In addition, retrieved data on TCGA implied co-occurrence of genomic alterations of AEG-1 and PPP6c in glioblastoma. Our findings indicate that AEG-1 is positively correlated with CD133 and AEG-1 expression. It may play an important role in the progression of glioma and may serve as potential novel marker of chemoresistance and radioresistance.
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Standard plane localization in ultrasound by radial component model and selective search.
Ultrasound Med Biol
PUBLISHED: 01-25-2014
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Acquisition of the standard plane is crucial for medical ultrasound diagnosis. However, this process requires substantial experience and a thorough knowledge of human anatomy. Therefore it is very challenging for novices and even time consuming for experienced examiners. We proposed a hierarchical, supervised learning framework for automatically detecting the standard plane from consecutive 2-D ultrasound images. We tested this technique by developing a system that localizes the fetal abdominal standard plane from ultrasound video by detecting three key anatomical structures: the stomach bubble, umbilical vein and spine. We first proposed a novel radial component-based model to describe the geometric constraints of these key anatomical structures. We then introduced a novel selective search method which exploits the vessel probability algorithm to produce probable locations for the spine and umbilical vein. Next, using component classifiers trained by random forests, we detected the key anatomical structures at their probable locations within the regions constrained by the radial component-based model. Finally, a second-level classifier combined the results from the component detection to identify an ultrasound image as either a "fetal abdominal standard plane" or a "non- fetal abdominal standard plane." Experimental results on 223 fetal abdomen videos showed that the detection accuracy of our method was as high as 85.6% and significantly outperformed both the full abdomen and the separate anatomy detection methods without geometric constraints. The experimental results demonstrated that our system shows great promise for application to clinical practice.
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Arbuscular mycorrhizal fungal phylogenetic groups differ in affecting host plants along heavy metal levels.
J Environ Sci (China)
PUBLISHED: 01-22-2014
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Arbuscular mycorrhizal fungi (AMF) are important components of soil microbial communities, and play important role in plant growth. However, the effects of AMF phylogenetic groups (Glomeraceae and non-Glomeraceae) on host plant under various heavy metal levels are not clear. Here we conducted a meta-analysis to compare symbiotic relationship between AMF phylogenetic groups (Glomeraceae and non-Glomeraceae) and host plant functional groups (herbs vs. trees, and non-legumes vs. legumes) at three heavy metal levels. In the meta-analysis, we calculate the effect size (ln(RR)) by taking the natural logarithm of the response ratio of inoculated to non-inoculated shoot biomass from each study. We found that the effect size of Glomeraceae increased, but the effect size of non-Glomeraceae decreased under high level of heavy metal compared to low level. According to the effect size, both Glomeraceae and non-Glomeraceae promoted host plant growth, but had different effects under various heavy metal levels. Glomeraceae provided more benefit to host plants than non-Glomeraceae did under heavy metal condition, while non-Glomeraceae provided more benefit to host plants than Glomeraceae did under no heavy metal. AMF phylogenetic groups also differed in promoting plant functional groups under various heavy metal levels. Interacting with Glomeraceae, herbs and legumes grew better than trees and non-legumes did under high heavy metal level, while trees and legumes grew better than herbs and non-legumes did under medium heavy metal level. Interacting with non-Glomeraceae, herbs and legumes grew better than trees and non-legumes did under no heavy metal. We suggested that the combination of legume with Glomeraceae could be a useful way in the remediation of heavy metal polluted environment.
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Bioinformatic analysis of microRNA expression in Parkinson's disease.
Mol Med Rep
PUBLISHED: 01-19-2014
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Parkinson's disease (PD) is a type of movement disorder caused by loss of dopamine?producing neurons in the midbrain. In order to identify the synergistic microRNA (miRNA) pattern in PD, miRNA and mRNA double expression profiles of PD were downloaded. Differentially expressed miRNA and mRNA were identified [P<0.01, following false discovery rate (FDR) correction]. A cumulative hypergeometric distribution test was then performed to identify synergistic miRNAs (P<0.01, following FDR correction). Gene ontology (GO) function and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway annotations were performed to analyze the miRNA regulatory target genes. Subsequently, a synergistic miRNA network was constructed and miRNAs exhibiting a high degree were identified. In total, 200 differentially expressed miRNA and 2,966 differentially expressed mRNA were identified. In addition, 1,502 synergistic miRNA interactions were identified, and miRNAs regulated 304 target genes in total. The GO and KEGG analysis demonstrated that these target genes were enriched in biosynthetic and cellular biosynthetic processes, the assembly of cellular components in morphogenesis, mitogen?activated protein kinase signaling, myometrial relaxation and contraction pathways as well as calcium regulation. The miRNA network demonstrated that miR?627, miR?634, miR?514, miR?563 and miR?613 had a high degree. miRNA with a high degree may be associated with the pathogenesis of PD and, therefore, may assist in the diagnosis and therapy of PD.
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IL-10 Deficiency Increases Renal Ischemia-Reperfusion Injury.
Nephron Exp. Nephrol.
PUBLISHED: 01-17-2014
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Background: Renal ischemia-reperfusion (IR) injury is a frequent cause of acute kidney injury, which results in high morbidity and mortality. Inflammation is an important factor that is involved in kidney repair after renal IR injury. IL-10 is a potent anti-inflammatory cytokine that inhibits inflammatory pathways, but the role of IL-10 in repairing renal IR injury is not known. Here, we investigated the role of IL-10 in kidney repair after renal IR injury. Methods: We used an IL-10(-/-) mouse model and examined the serologic and histomorphology of kidney after IR injury. We also measured ki67, TNF-?, IL-6, and macrophages with immunohistochemistry or Western blotting. Results: There was a greater increase in serum creatinine in IL-10(-/-) mice than in wild-type (WT) mice. And compared with WT mice, IL-10(-/-) mice had increased histologic renal injury and decreased proliferation. Moreover, the expression of TNF-?, IL-6 and macrophages was clearly increased in IL-10(-/-) mice compared with the WT mice. Conclusion: These data reveal an important role for IL-10 in the improvement of renal IR injury, acting through suppression of inflammatory mediators, and that IL-10 would be a crucial target for the treatment of IR injury. © 2014 S. Karger AG, Basel.
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The roles of mitoferrin-2 in the process of arsenic trioxide-induced cell damage in human gliomas.
Eur. J. Med. Res.
PUBLISHED: 01-10-2014
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BackgroundAmong glioma treatment strategies, arsenic trioxide (As2O3) has shown efficacy as a therapeutic agent against human gliomas. However, the exact antitumor mechanism of action of As2O3 is still unclear. Mitochondria are considered to be the major source of intracellular reactive oxygen species (ROS), which are known to be associated with As2O3-induced cell damage. Therefore, we investigated whether mitoferrin-2, a mitochondrial iron uptake transporter, participates in As2O3-induced cell killing in human gliomas.MethodsHuman glioma cell lines were used to explore the mechanism of As2O3¿s antitumor effects. First, expression of mitoferrin-2 was analyzed in glioma cells that were pretreated with As2O3. Changes in ROS production and apoptosis were assessed. Furthermore, cell viability was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT).ResultsIn the present study we found that As2O3 induced ROS production and apoptosis in glioma cells. In addition, gene expression of mitoferrin-2, a mitochondrial iron uptake transporter, was increased 4 to 5 fold after exposure to As2O3 (5 ¿M) for 48 hours. Furthermore, apoptosis and cytotoxicity induced by As2O3 in glioma cells were decreased after silencing the mitoferrin-2 gene.ConclusionsOur findings indicated that mitoferrin-2 participates in mitochondrial ROS-dependent mechanisms underlying As2O3-mediated damage in glioma cells.
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A Functional Polymorphism C-509T in TGF?-1 Promoter Contributes to Susceptibility and Prognosis of Lone Atrial Fibrillation in Chinese Population.
PLoS ONE
PUBLISHED: 01-01-2014
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Transforming growth factor-?1 (TGF-?1) is an important mediator of atrial fibrosis and atrial fibrillation (AF). But the involved genetic mechanism is unknown. Herein, the TGF-?1 C-509T polymorphism (rs1800469) was genotyped in a case-control study of 840 patients and 845 controls in Chinese population to explore the association between the polymorphism and susceptibility and prognosis of lone AF. As a result, the CT and/or TT genotypes had an increased lone AF risk [adjusted odds ratio (OR)?=?1.50 for CT, OR?=?3.72 for TT, and OR?=?2.15 for CT/TT], compared with the TGF-?1CC genotype. Moreover, patients carrying CT/TT genotypes showed a higher possibility of AF recurrence after catheter ablation, compared with patients carrying CC genotype. In a genotype-phenotype correlation analysis using 24 normal left atrial appendage samples, increasing gradients of atrial TGF-?1 expression levels positively correlated with atrial collagen volume fraction were identified in samples with CC, CT and TT genotypes. The in vitro luciferase assays also showed a higher luciferase activity of the -509T allele than that of the -509C allele. In conclusion, the TGF-?1 C-509T polymorphism is involved in the etiology of lone AF and thus may be a marker for genetic susceptibility to lone AF and predicting prognosis after catheter ablation in Chinese populations. Therefore, we provide new information about treatment strategies and our understanding of TGF-?1 in AF.
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Fusarochromanone Induces G1 Cell Cycle Arrest and Apoptosis in COS7 and HEK293 Cells.
PLoS ONE
PUBLISHED: 01-01-2014
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Fusarochromanone (FC101), a mycotoxin produced by the fungus Fusarium equiseti, is frequently observed in the contaminated grains and feedstuffs, which is toxic to animals and humans. However, the underlying molecular mechanism remains to be defined. In this study, we found that FC101 inhibited cell proliferation and induced cell death in COS7 and HEK293 cells in a concentration-dependent manner. Flow cytometric analysis showed that FC101 induced G1 cell cycle arrest and apoptosis in the cells. Concurrently, FC101 downregulated protein expression of cyclin D1, cyclin-dependent kinases (CDK4 and CDK6), and Cdc25A, and upregulated expression of the CDK inhibitors (p21Cip1 and p27Kip1), resulting in hypophosphorylation of Rb. FC101 also inhibited protein expression of Bcl-2, Bcl-xL, Mcl-1 and survivin, and induced expression of BAD, leading to activation of caspase 3 and cleavage of PARP, indicating caspase-dependent apoptosis. However, Z-VAD-FMK, a pan-caspase inhibitor, only partially prevented FC101-induced cell death, implying that FC101 may induce cell death through both caspase-dependent and -independent mechanisms. Our results support the notion that FC101 executes its toxicity at least by inhibiting cell proliferation and inducing cell death.
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Prenatal Exposure to Lipopolysaccharide Results in Local RAS Activation in the Adipose Tissue of Rat Offspring.
PLoS ONE
PUBLISHED: 01-01-2014
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Adult metabolic syndrome may originate in part during fetal or early life. This study was designed to investigate the effects of prenatal exposure to lipopolysaccharide (LPS) on adipose development and local renin-angiotensin system (RAS) activation in rat offspring.
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Evaluation of spasticity after stroke by using ultrasound to measure the muscle architecture parameters: a clinical study.
Int J Clin Exp Med
PUBLISHED: 01-01-2014
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This study aims to compare the difference and the change trend of Muscle Architecture Parameters (MAP) between spastic and normal muscle tone patients after stroke, and analysis the application and value of Muscle Architecture Parameters in evaluating spasticity after stroke.
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Upregulation of neuregulin-1 reverses signs of neuropathic pain in rats.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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Peripheral nerve injury can result in neuropathic pain, a chronic condition of unclear cause often poorly responsive to current treatments. One possibility is that nerve injury disrupts large A-fiber-mediated inhibition of C-fiber-evoked responses in spinal dorsal horn neurons, leading to central sensitization. A recent study provided a potential molecular mechanism; large dorsal root ganglion (DRG) neurons secrete neuregulin-1 (NRG1), which binds to erbB4 receptors on interneurons and promotes GABA release to inhibit C-fiber-evoked nociceptive transmission. Thus, reduced NRG1 expression following nerve injury could induce chronic pain by disinhibition. We examined if DRG expression of NRG1 is in fact reduced in a rat model of neuropathic pain and if exogenous NRG1 alleviates behavioral signs of this condition.
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Transcriptome sequencing and identification of cold tolerance genes in hardy Corylus species (C. heterophylla Fisch) floral buds.
PLoS ONE
PUBLISHED: 01-01-2014
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The genus Corylus is an important woody species in Northeast China. Its products, hazelnuts, constitute one of the most important raw materials for the pastry and chocolate industry. However, limited genetic research has focused on Corylus because of the lack of genomic resources. The advent of high-throughput sequencing technologies provides a turning point for Corylus research. In the present study, we performed de novo transcriptome sequencing for the first time to produce a comprehensive database for the Corylus heterophylla Fisch floral buds.
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Role of HERP and a HERP-related protein in HRD1-dependent protein degradation at the endoplasmic reticulum.
J. Biol. Chem.
PUBLISHED: 12-23-2013
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Misfolded proteins of the endoplasmic reticulum (ER) are retrotranslocated to the cytosol and degraded by the proteasome via a process termed ER-associated degradation (ERAD). The precise mechanism of retrotranslocation is unclear. Here, we use several lumenal ERAD substrates targeted for degradation by the ubiquitin ligase HRD1 including sonic hedgehog (SHH) and NHK to study the geometry, organization, and regulation of the HRD1-containing ERAD machinery. We report a new HRD1-associated membrane protein named HERP2, which is homologous to the previously identified HRD1 partner HERP1. Despite sequence homology, HERP2 is constitutively expressed in cells whereas HERP1 is highly induced by ER stress. We find that these proteins are required for efficient degradation of both glycosylated and non-glycosylated SHH proteins as well as NHK. In cells depleted of HERPs, SHH proteins are largely trapped inside the ER with a fraction of the stabilized SHH protein bound to the HRD1-SEL1L ligase complex. Ubiquitination of SHH is significantly attenuated in the absence of HERPs, suggesting a defect in retrotranslocation. Both HERP proteins interact with HRD1 through a region located in the cytosol. However, unlike its homolog in S. cerevisiae, HERPs do not regulate HRD1 stability or oligomerization status. Instead, they help recruit DERL2 to the HRD1-SEL1L complex. Additionally, the UBL domain of HERP1 also seems to have a function independent of DERL2 recruitment in ERAD. Our studies have revealed a critical scaffolding function for mammalian HERP proteins that is required for forming an active retrotranslocation complex containing HRD1, SEL1L, and DERL2.
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[A clinical study of preoperative prophylactic application of intra-aortic balloon pump in extreme high-risk patients undergoing coronary artery bypass grafting].
Zhonghua Wai Ke Za Zhi
PUBLISHED: 12-17-2013
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To compare the clinical outcome between the intra-aortic balloon pump (IABP) inserted in the preoperative prophylactic condition and in the emergent condition for the patients with extreme high risks undergoing coronary artery bypass grafting (CABG).
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[The surgical strategy for laparoscopic approach in recurrent inguinal hernia repair: 213 cases report].
Zhonghua Wai Ke Za Zhi
PUBLISHED: 12-17-2013
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To evaluate the surgical strategy for laparoscopic approach in recurrent inguinal hernia repair.
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