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Find video protocols related to scientific articles indexed in Pubmed.
Characterization of Alpha Toxin hla Gene Variants, Alpha Toxin Expression Levels and Antibody Levels to Alpha Toxin in Hemodialysis and Post-Surgical Patients with Staphylococcus aureus Bacteremia.
J. Clin. Microbiol.
PUBLISHED: 11-14-2014
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Alpha-toxin is a major Staphylococcus aureus virulence factor. This study evaluated potential relationships between in vitro ?-toxin expression of S. aureus bloodstream isolates, anti-?-toxin antibody in serum of patients with S. aureus bacteremia (SAB), and clinical outcome in 100 hemodialysis and 100 post-surgical SAB patients. Isolates underwent spa-typing and hla sequencing. Serum anti-?-toxin IgG and neutralizing antibody levels were measured using ELISA and RBC-based hemolysis neutralization assay. Neutralization of ?-toxin by anti-?-toxin mAb (MEDI4893) was tested in an RBC-based lysis assay. Most isolates encoded hla (197/200; 98.5%) and expressed ?-toxin (173/200; 86.5%). In vitro ?-toxin levels were inversely associated with survival (Cure: 2.19 ?g/ml vs. Failure: 1.09 ?g/ml; P < 0.01). Both neutralizing (Hemodialysis: 1.26 IU/ml vs. Post-surgical: 0.95; P<0.05) and IgG (Hemodialysis: 1.94 IU/ml vs. Post-surgical: 1.27; P<0.05) antibody levels were higher in the hemodialysis population. Antibody levels were also significantly higher in patients infected with ?-toxin-expressing S. aureus isolates (P<0.05). Levels of both neutralizing antibodies and IgG were similar among patients that were cured and not cured (failures). Sequence analysis of hla revealed 12 distinct hla genotypes and all genotypic variants were susceptible to a neutralizing monoclonal antibody in clinical development (MEDI4893). These data demonstrate that ?-toxin is highly conserved in clinical S. aureus isolates. Higher in vitro ?-toxin levels were associated with a positive clinical outcome. Although patients infected with ?-toxin-producing S. aureus exhibited higher anti-?-toxin antibody levels, these levels were not associated with a better clinical outcome in this study.
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Analysis of poly-?-hydroxyalkonates (PHA) during the enhanced biological phosphorus removal process using FTIR spectroscopy.
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 11-01-2014
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Enhanced biological phosphorus removal (EBPR) is the main phosphorus removal technique for wastewater treatment. During the anaerobic-aerobic alternative process, the activated sludge experienced the anaerobic storage of polyhydroxy-?-alkonates (PHA) and aerobic degradation, corresponding the infrared peak intensity of sludge at 1 740 cm(-1) increased in the aerobic phase and declined in the anaerobic phase. Compared with PHA standard, this peak was indentified to attribute the carbonyl of PHA. The overlapping peaks of PHA, protein I and II bands were separated using Gaussian peak fitting method. The infrared peak area ratios of PHA versus protein I had a good relationship with the PHA contents measured by gas chromatography, and the correlation coefficient was 0.873. Thus, the ratio of the peak area of PHA versus protein I can be considered as the indicator of the PHA content in the sludge. The infrared spectra of 1 480-1 780 cm(-1) was selected, normalized and transferred to the absorption data. Combined with the chromatography analysis of PHA content in the sludge sample, a model between the Fourier-transform infrared spectroscopy (ETIR) spectra of the sludge and PHA content was established, which could be used for the prediction of the PHA content in the unknown sample. The PHA content in the sludge sample could be acquired by the infrared spectra of the sludge sample and the established model, and the values fitted well with the results obtained from chromatograph. The results would provide a novel analysis method for the rapid characterization and quantitative determination of the intracellular PHA content in the activated sludge.
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Suppression of esophageal tumor growth and chemoresistance by directly targeting the PI3K/AKT pathway.
Oncotarget
PUBLISHED: 10-27-2014
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Esophageal cancer is the sixth most common cause of cancer-related deaths worldwide. Novel therapeutic intervention is urgently needed for this deadly disease. The functional role of PI3K/AKT pathway in esophageal cancer is little known. In this study, our results from 49 pairs of human esophageal tumor and normal specimens demonstrated that AKT was constitutively active in the majority (75.5%) of esophageal tumors compared with corresponding normal tissues. Inhibition of the PI3K/AKT pathway with specific inhibitors, wortmannin and LY294002, significantly reduced Bcl-xL expression, induced caspase-3-dependent apoptosis, and repressed cell proliferation and tumor growth in vitro and in vivo without obvious toxic effects. Moreover, significantly higher expression level of p-AKT was observed in fluorouracil (5-FU)-resistant esophageal cancer cells. Inactivation of PI3K/AKT pathway markedly increased the sensitivity and even reversed acquired resistance of esophageal cancer cells to chemotherapeutic drugs in vitro. More importantly, the resistance of tumor xenografts derived from esophageal cancer cells with acquired 5-FU resistance to chemotherapeutic drugs was significantly abrogated by wortmannin treatment in animals. In summary, our data support PI3K/AKT as a valid therapeutic target and strongly suggest that PI3K/AKT inhibitors used in conjunction with conventional chemotherapy may be a potentially useful therapeutic strategy in treating esophageal cancer patients.
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Direct intramolecular conjugate addition of simple alkenes to ?,?-unsaturated carbonyls catalyzed by Cu(OTf)2.
Org. Lett.
PUBLISHED: 09-22-2014
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An unprecedented intramolecular conjugate addition of simple alkenes to ?,?-unsaturated carbonyl compounds has been developed. A simple Lewis acid such as Cu(OTf)2 was found to effectively catalyze the reaction, and six- and five-membered cyclic products were obtained in moderate to high yields.
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A leucine residue in the C terminus of human parainfluenza virus type 3 matrix protein is essential for efficient virus-like particle and virion release.
J. Virol.
PUBLISHED: 09-03-2014
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Paramyxovirus particles, like other enveloped virus particles, are formed by budding from membranes of infected cells, and matrix (M) proteins are critical for this process. To identify the M protein important for this process, we have characterized the budding of the human parainfluenza virus type 3 (HPIV3) M protein. Our results showed that expression of the HPIV3 M protein alone is sufficient to initiate the release of virus-like particles (VLPs). Electron microscopy analysis confirmed that VLPs are morphologically similar to HPIV3 virions. We identified a leucine (L302) residue within the C terminus of the HPIV3 M protein that is critical for M protein-mediated VLP production by regulating the ubiquitination of the M protein. When L302 was mutated into A302, ubiquitination of M protein was defective, the release of VLPs was abolished, and the membrane binding and budding abilities of M protein were greatly weakened, but the ML302A mutant retained oligomerization activity and had a dominant negative effect on M protein-mediated VLP production. Furthermore, treatment with a proteasome inhibitor also inhibited M protein-mediated VLP production and viral budding. Finally, recombinant HPIV3 containing the ML302A mutant could not be rescued. These results suggest that L302 acts as a critical regulating signal for the ubiquitination of the HPIV3 M protein and virion release.
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Optimization of medium composition for cis,cis-muconic acid production by a Pseudomonas sp. mutant using statistical methods.
Prep. Biochem. Biotechnol.
PUBLISHED: 08-29-2014
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cis,cis-Muconic acid (CCMA) is used as a platform chemical for the production of several high-value compounds. For this article, an optimization strategy has been used to optimize medium composition for CCMA production from fairly cheap benzoate by Pseudomonas sp. 1167. The effect of different concentrations of medium components on CCMA production was studied. CCMA yields obtained from Plackett-Burman design (PBD) showed wide variation (3.95-5.87 g/L), and the first-order model indicated that (NH(4))(2)SO(4) (P < 0.01) and K(2)HPO(4) · 3H(2)O (P < 0.02) were the significant components for CCMA production. Then the optimization was performed by steepest ascent design (SAD) and central composite design (CCD), and a validation experiment was conducted to verify the predicted value. The optimal medium composition was: 12 g/L sodium benzoate, 2.5 g/L sodium succinate, 0.7932 g/L (NH(4))(2)SO(4), 1.5612 g/L K(2)HPO(4) · 3H(2)O, 1.2 g/L MgSO(4) · 7H(2)O, 0.4 g/L yeast extract, 0.08 g/L FeCl(3) · 6H(2)O, and 0.08 g/L ethylenediamine tetraacetic acid (EDTA). Under these conditions, a maximum of 7.18 g/L CCMA was produced per 12 g/L benzoate with a highly efficient process within 11 hr and a molecular conversion yield of 61%. Altogether, our results provide valuable insights into nutritional supplementation of CCMA production by using statistical methods, which may benefit a cost-competitive industrial fed-batch fermentation process using a cheap substrate.
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Ghrelin promotes hepatic lipogenesis by activation of mTOR-PPAR? signaling pathway.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 08-25-2014
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Although ghrelin has been demonstrated to stimulate energy intake and storage through a central mechanism, its effect on hepatic lipid metabolism remains largely uncharacterized. Ghrelin receptor antagonism or gene deletion significantly decreased obesity-associated hepatic steatosis by suppression of de novo lipogenesis, whereas exogenous ghrelin stimulated lipogenesis, leading to hepatic lipid accumulation in mice. The effects of ghrelin were mediated by direct activation of its receptor on hepatocytes. Cultured hepatocytes responded to ghrelin with increased lipid content and expression of lipogenesis-related genes. Ghrelin increased phosphorylation of S6, the downstream target of mammalian target of rapamycin (mTOR) signaling in cultured hepatocytes, whereas ghrelin receptor antagonism reduced hepatic phosphorylation of S6 in db/db mice. Inhibition of mTOR signaling by rapamycin markedly attenuated ghrelin-induced up-regulation of lipogenesis in hepatocytes, whereas activation of hepatic mTOR signaling by deletion of TSC1 increased hepatic lipogenesis. By interacting with peroxisome proliferator-activated receptor-? (PPAR?), mTOR mediates the ghrelin-induced up-regulation of lipogenesis in hepatocytes. The stimulatory effect of ghrelin on hepatic lipogenesis was significantly attenuated by PPAR? antagonism in cultured hepatocytes and in PPAR? gene-deficient mice. Our study indicates that ghrelin activates its receptor on hepatocytes to promote lipogenesis via a mechanism involving the mTOR-PPAR? signaling pathway.
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Myeloid-specific disruption of RBP-J ameliorates hepatic fibrosis by attenuating inflammation through cylindromatosis in mice.
Hepatology
PUBLISHED: 08-22-2014
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Macrophages play multi-dimensional roles in hepatic fibrosis, but their control has not been fully understood. Literatures have shown that the Notch pathway mediated by RBP-J, the transcription factor transactivated by signals from four mammalian Notch receptors, is implicated in macrophage activation and plasticity. In this study, by using mouse hepatic fibrosis models, we show that myeloid-specific disruption of RBP-J resulted in attenuated fibrosis. The activation of hepatic stellate cells and production of pro-fibrotic factors including PDGF-B and TGF-?1 reduced significantly in myeloid-specific RBP-J deficient mice. The infiltration of inflammatory cells and production of pro-inflammatory factors reduced in liver of myeloid-specific RBP-J deficient mice during fibrosis. In RBP-J deficient macrophages, the NF-?B activation was remarkably attenuated as compared with the control. This could be attributed to the upregulation of cylindromatosis (CYLD), a negative regulator of NF-?B, in Notch signal-compromised macrophages, because the knockdown of CYLD in RBP-J-deficient macrophages or overexpression of p65 in RBP-J knockdown cells both restored NF-?B activation and the production of pro-inflammatory and/or pro-fibrotic factors by macrophages. In human hepatic fibrosis biopsies, stronger Notch activation is correlated with more severe fibrosis, which is accompanied by lower level of CYLD but irrespective of etiological reasons. Conclusion: RBP-J-mediated Notch signaling is required for macrophages to promote hepatic fibrosis by up-regulation of NF-?B activation through CYLD. (Hepatology 2014).
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Myeloid-Specific Blockade of Notch Signaling by RBP-J Knockout Attenuates Spinal Cord Injury Accompanied by Compromised Inflammation Response in Mice.
Mol. Neurobiol.
PUBLISHED: 08-19-2014
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The outcome of spinal cord injury (SCI) is determined by both neural cell-intrinsic survival pathways and tissue microenvironment-derived signals. Macrophages dominating the inflammatory responses in SCI possess both destructive and reparative potentials, according to their activation status. Notch signaling is involved in both cell survival and macrophage-mediated inflammation, but a comprehensive role of Notch signaling in SCI has been elusive. In this study, we compared the effects of general Notch blockade by a pharmaceutical ?-secretase inhibitor (GSI) and myeloid-specific Notch signal disruption by recombination signal binding protein J? (RBP-J) knockout on SCI. The administration of Notch signal inhibitor GSI resulted in worsened hind limb locomotion and exacerbated inflammation. However, mice lacking RBP-J, the critical transcription factor mediating signals from all four mammalian Notch receptors, in myeloid lineage displayed promoted functional recovery, attenuated glial scar formation, improved neuronal survival and axon regrowth, and mitigated inflammatory response after SCI. These benefits were accompanied by enhanced AKT activation in the lesion area after SCI. These findings demonstrate that abrogating Notch signal in myeloid cells ameliorates inflammation response post-SCI and promotes functional recovery, but general pharmaceutical Notch interception has opposite effects. Therefore, clinical intervention of Notch signaling in SCI needs to pinpoint myeloid lineage to avoid the counteractive effects of global inhibition.
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EF-G catalyzes tRNA translocation by disrupting interactions between decoding center and codon-anticodon duplex.
Nat. Struct. Mol. Biol.
PUBLISHED: 08-10-2014
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During translation, elongation factor G (EF-G) catalyzes the translocation of tRNA2-mRNA inside the ribosome. Translocation is coupled to a cycle of conformational rearrangements of the ribosomal machinery, and how EF-G initiates translocation remains unresolved. Here we performed systematic mutagenesis of Escherichia coli EF-G and analyzed inhibitory single-site mutants of EF-G that preserved pretranslocation (Pre)-state ribosomes with tRNAs in A/P and P/E sites (Pre-EF-G). Our results suggest that the interactions between the decoding center and the codon-anticodon duplex constitute the barrier for translocation. Catalysis of translocation by EF-G involves the factor's highly conserved loops I and II at the tip of domain IV, which disrupt the hydrogen bonds between the decoding center and the duplex to release the latter, hence inducing subsequent translocation events, namely 30S head swiveling and tRNA2-mRNA movement on the 30S subunit.
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Circulating levels of miR-146a and IL-17 are significantly correlated with the clinical activity of Graves' ophthalmopathy.
Endocr. J.
PUBLISHED: 08-08-2014
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Graves' ophthalmopathy (GO) is a common autoimmune disease that is difficult to deal with due to limited clinical evaluation methods. Recently miR-146a and Interleukin-17 (IL-17) have been found to be involved in autoimmune disorders and correlated with disease activity. However, it is unclear whether they are involved in Graves' ophthalmopathy (GO). The aim of this study is to investigate the correlation of circulating levels of miR-146a and IL-17 with clinical activity in GO patients. Fifty-seven study subjects were enrolled in four groups according to the corresponding criteria: active-GO, inactive-GO, Graves disease (GD) without ophthalmopathy, and healthy control group. The circulating levels of miR-146a and IL-17 were determined by qRT-PCR and ELISA, respectively. Serum IL-17 levels of GD, inactive-GO, and active-GO groups were all significantly higher than that of control (all P<0.001). Active-GO group had significantly higher IL-17 level than inactive-GO and GD groups (P=0.024 and P=0.001, respectively). Active-GO and inactive-GO group had significantly lower miR-146a expressions than control (P<0.05). Active-GO group had significantly lower miR-146a than inactive-GO group (P<0.05). Serum levels of IL-17 and miR-146a were both significantly correlated with CAS in GO patients (P<0.001, P<0.001, respectively). There was a significant negative correlation of circulating miR-146a expression with serum IL-17 levels (P<0.01). These findings indicated that circulating levels of miR-146a and IL-17 may be potential biomarkers of active GO, and may play a key role in the progression of GO.
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HIV-1 Nef and KSHV oncogene K1 synergistically promote angiogenesis by inducing cellular miR-718 to regulate the PTEN/AKT/mTOR signaling pathway.
Nucleic Acids Res.
PUBLISHED: 08-07-2014
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Kaposi's sarcoma (KS) is an AIDS-defining cancer with aberrant neovascularization caused by KS-associated herpesvirus (KSHV). Although the interaction between HIV-1 and KSHV plays a pivotal role in promoting the aggressive manifestations of KS, the pathogenesis underlying AIDS-KS remains largely unknown. Here we examined HIV-1 Nef protein promotion of KSHV oncoprotein K1-induced angiogenesis. We showed that both internalized and ectopic expression of Nef in endothelial cells synergized with K1 to facilitate vascular tube formation and cell proliferation, and enhance angiogenesis in a chicken CAM model. In vivo experiments further indicated that Nef accelerated K1-induced angiogenesis and tumorigenesis in athymic nu/nu mice. Mechanistic studies revealed that Nef and K1 synergistically activated PI3K/AKT/mTOR signaling by downregulating PTEN. Furthermore, Nef and K1 induced cellular miR-718, which inhibited PTEN expression by directly targeting a seed sequence in the 3' UTR of its mRNA. Inhibition of miR-718 expression increased PTEN synthesis and suppressed the synergistic effect of Nef- and K1-induced angiogenesis and tumorigenesis. These results indicate that, by targeting PTEN, miR-718 mediates Nef- and K1-induced angiogenesis via activation of AKT/mTOR signaling. Our results demonstrate an essential role of miR-718/AKT/mTOR axis in AIDS-KS and thus may represent an attractive therapeutic target.
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Long-term use of ciclosporin on kidney transplant recipients surviving more than 10 years.
Pharmazie
PUBLISHED: 07-31-2014
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To evaluate the long-term use of ciclosporin on kidney transplant recipients who survived more than 10 years.
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Small circular DNA molecules act as rigid motifs to build DNA nanotubes.
J. Am. Chem. Soc.
PUBLISHED: 07-10-2014
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Small circular DNA molecules with designed lengths, for example 64 and 96 nucleotides (nt), after hybridization with a few 32-nt staple strands respectively, can act as rigid motifs for the construction of DNA nanotubes with excellent uniformity in ring diameter. Unlike most native DNA nanotubes, which consist of longitudinal double helices, nanotubes assembled from circular DNAs are constructed from lateral double helices. Of the five types of DNA nanotubes designed here, four are built by alternating two different rings of the same ring size, while one is composed of all the same 96-nt rings. Nanotubes constructed from the same 96-nt rings are 10-100 times shorter than those constructed from two different 96-nt rings, because there are fewer hinge joints on the rings.
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Prognostic Significance of Pretreatment Plasma Fibrinogen and Platelet Levels in Patients with Early-Stage Cervical Cancer.
Gynecol. Obstet. Invest.
PUBLISHED: 06-25-2014
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Background: Hyperfibrinogenaemia and thrombocytosis, which usually occur in cancer patients, have been shown to contribute to cancer cell growth, progression, and metastasis. The aims of the present study were to assess the prognostic significance of pretreatment plasma fibrinogen and platelet levels in early-stage cervical cancer patients. Methods: The present study was a retrospective analysis of 220 cervical cancer patients with stage I-IIA disease. The pretreatment plasma fibrinogen and platelet levels were investigated along with clinicopathological findings and survival data. Results: The incidences of hyperfibrinogenaemia and thrombocytosis were 11.8 and 25.5%, respectively. Elevated fibrinogen levels were associated with advanced tumour stage, older age, large tumour size, deep stromal invasion, and tumour recurrence, whereas higher platelet levels correlated significantly with advanced tumour stage, large tumour size, and tumour recurrence. Kaplan-Meier analysis showed that hyperfibrinogenaemia and thrombocytosis were significantly associated with shorter disease-free and overall survival. Furthermore, patients with hyperfibrinogenaemia and thrombocytosis may suffer from a higher risk of recurrence. Multivariate survival analyses showed that fibrinogen levels, but not platelet levels, were an independent prognostic factor for poor survival in early-stage patients. Conclusion: Hyperfibrinogenaemia and thrombocytosis may be valuable biomarkers for predicting recurrence in patients with early-stage cervical cancer. © 2014 S. Karger AG, Basel.
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FHL1C induces apoptosis in Notch1-dependent T-ALL cells through an interaction with RBP-J.
BMC Cancer
PUBLISHED: 06-17-2014
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Aberrantly activated Notch signaling has been found in more than 50% of patients with T-cell acute lymphoblastic leukemia (T-ALL). Current strategies that employ ?-secretase inhibitors (GSIs) to target Notch activation have not been successful. Many limitations, such as non-Notch specificity, dose-limiting gastrointestinal toxicity and GSI resistance, have prompted an urgent need for more effective Notch signaling inhibitors for T-ALL treatment. Human four-and-a-half LIM domain protein 1C (FHL1C) (KyoT2 in mice) has been demonstrated to suppress Notch activation in vitro, suggesting that FHL1C may be new candidate target in T-ALL therapy. However, the role of FHL1C in T-ALL cells remained unclear.
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Detection and Chemical Profiling of Ling-Gui-Zhu-Gan Decoction by Ultra Performance Liquid Chromatography-Hybrid Linear Ion Trap-Orbitrap Mass Spectrometry.
J Chromatogr Sci
PUBLISHED: 06-13-2014
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Ling-Gui-Zhu-Gan decoction (LGZGD), a well-known traditional Chinese medicine (TCM) formula, has been extensively used for the treatment of cardiovascular disease in clinic. However, the chemical constituents in LGZGD had not been investigated so far. In this study, an ultra performance liquid chromatography-hybrid electrospray ionization linear ion trap-Orbitrap mass spectrometry (UPLC-LTQ-Oribitrap-MS/MS) method was established for rapid separation and structural identification of the constituents in LGZGD. Separation was performed on an ACQUITY(TM) UPLC BEH C18 column (50 × 2.1 mm, 1.7 ?m) by gradient elution mode, using acetonitrile-water containing 0.1% formic acid as mobile phase at the flow rate of 0.2 mL/min. Accurate mass measurement for molecular ions and characteristic fragment ions could represent identification criteria for these compounds. As a result, 95 compounds including triterpene acids, triterpene saponins, flavonoids, coumarins, coumestans, benzofurans, phenylpropanoids and sesquiterpenoid lactones were detected, and 90 of them were tentatively identified. All compounds were further assigned in the individual raw material. In conclusion, the UPLC-LTQ-Orbitrap-MS/MS is a highly efficient technique to separate and identify constituents in complex matrices of TCMs. These results obtained in this research will provide a basis for quality control and further in vivo study of LGZGD.
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Dusp3 and Psme3 are associated with murine susceptibility to Staphylococcus aureus infection and human sepsis.
PLoS Pathog.
PUBLISHED: 06-01-2014
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Using A/J mice, which are susceptible to Staphylococcus aureus, we sought to identify genetic determinants of susceptibility to S. aureus, and evaluate their function with regard to S. aureus infection. One QTL region on chromosome 11 containing 422 genes was found to be significantly associated with susceptibility to S. aureus infection. Of these 422 genes, whole genome transcription profiling identified five genes (Dcaf7, Dusp3, Fam134c, Psme3, and Slc4a1) that were significantly differentially expressed in a) S. aureus -infected susceptible (A/J) vs. resistant (C57BL/6J) mice and b) humans with S. aureus blood stream infection vs. healthy subjects. Three of these genes (Dcaf7, Dusp3, and Psme3) were down-regulated in susceptible vs. resistant mice at both pre- and post-infection time points by qPCR. siRNA-mediated knockdown of Dusp3 and Psme3 induced significant increases of cytokine production in S. aureus-challenged RAW264.7 macrophages and bone marrow derived macrophages (BMDMs) through enhancing NF-?B signaling activity. Similar increases in cytokine production and NF-?B activity were also seen in BMDMs from CSS11 (C57BL/6J background with chromosome 11 from A/J), but not C57BL/6J. These findings suggest that Dusp3 and Psme3 contribute to S. aureus infection susceptibility in A/J mice and play a role in human S. aureus infection.
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Nipple discharge of CA15-3, CA125, CEA and TSGF as a new biomarker panel for breast cancer.
Int J Mol Sci
PUBLISHED: 05-14-2014
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Breast cancer is the second leading cause of cancer death in women. Serum biomarkers such as cancer antigen 15-3 (CA15-3), cancer antigen 125 (CA125), and carcinoembryonic antigen (CEA) can be used as diagnostic and prognostic factors and can also provide valuable information during follow-up. However, serum protein biomarkers show limited diagnostic sensitivity and specificity in stand-alone assays because their levels reflect tumor burden. To validate whether biomarkers in nipple discharge may serve as novel biomarkers for breast cancer, we composed a panel of potential cancer biomarkers, including CA15-3, CA125, CEA, and malignant tumor-specific growth factor (TSGF), and evaluated their expression in both serum and nipple discharge in order to explore the expression and significance of estrogen receptor (ER), progestrone receptor (PR), epidermal growth factor receptor type 2 (HER2/neu), CA15-3, CA125, CEA, and TSGF expression for their combined predictive value for breast cancer and in judging the prognosis of breast cancer. Univariate analysis revealed that combined detection of CA15-3, CA125, CEA, and TSGF in nipple discharge served as novel biomarkers for the diagnosis and prognosis of breast cancer, but in the multivariate analyses the adverse effects of the four biomarkers combination in nipple discharge positivity on overall survival were lost. Multivariate analysis revealed that the positivity of the combined detection of the four biomarkers in both nipple discharge and serum was significantly higher than that of other detection methods. Thus, the combined detection of these four biomarkers both in serum and nipple discharge was retained as an independent prognostic variable in breast cancer patients. Our results indicate that CA15-3, CA125, CEA, and TSGF in nipple discharge can serve as novel biomarkers in the diagnosis and prognosis of breast cancer.
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Mitochondrial EF4 links respiratory dysfunction and cytoplasmic translation in Caenorhabditis elegans.
Biochim. Biophys. Acta
PUBLISHED: 05-08-2014
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How animals coordinate cellular bioenergetics in response to stress conditions is an essential question related to aging, obesity and cancer. Elongation factor 4 (EF4/LEPA) is a highly conserved protein that promotes protein synthesis under stress conditions, whereas its function in metazoans remains unknown. Here, we show that, in Caenorhabditis elegans, the mitochondria-localized CeEF4 (referred to as mtEF4) affects mitochondrial functions, especially at low temperature (15°C). At worms' optimum growing temperature (20°C), mtef4 deletion leads to self-brood size reduction, growth delay and mitochondrial dysfunction. Transcriptomic analyses show that mtef4 deletion induces retrograde pathways, including mitochondrial biogenesis and cytoplasmic translation reorganization. At low temperature (15°C), mtef4 deletion reduces mitochondrial translation and disrupts the assembly of respiratory chain supercomplexes containing complex IV. These observations are indicative of the important roles of mtEF4 in mitochondrial functions and adaptation to stressful conditions.
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[Efficacy and safety evaluation of gemcitabine combined with oxaliplatin in lymphoma patients after failure of multiple chemotherapy regimens].
Zhonghua Zhong Liu Za Zhi
PUBLISHED: 05-07-2014
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To evaluate the efficacy and safety of gemcitabine combined with oxaliplatin (GEMOX) in lymphoma patients after failure of multiple chemotherapy regimens.
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The prognostic utility and the association of serum light chains (free and total) and absolute lymphocyte count in patients with newly diagnosed diffuse large B-cell lymphoma.
Leuk. Res.
PUBLISHED: 05-06-2014
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In this study, serum free and total light chains (sFLC/sTLC) were measured in 108 serum samples of therapy-naïve patients with DLBCL. Clinicopathologic data and survival outcomes were analyzed according to the results of sFLC/sTLC measurements. Moreover, the association of sFLC/sTLC with absolute monocyte count (AMC) and absolute lymphocyte count (ALC) was evaluated. Elevated sFLC and abnormal ?/? ratio was present in 42.6% (51/108) and 4.6% (5/108) of patients, respectively. sTLC was successfully measured in 107 serum samples, abnormal sTLC and abnormal ?/? ratio was found in 28.0% (30/107) and 26.2% (28/107) of patients, respectively. Patients with elevated sFLC more frequently displayed adverse clinical characteristics, including age (P=0.001), B symptoms (P=0.022), low ALC (P=0.024) and hyperglobulinemia (P=0.012). Patients with elevated sFLC had an inferior overall survival (OS) (P=0.012) and tended to have shorter progression-free survival (PFS) (P=0.061) compared to patients with normal sFLC. Abnormal sTLC or abnormal sTLC ratio showed no significant association with clinical outcomes, with exception of abnormal concurrent ? and ?. Only association of sFLC and ALC with survival remained significant after adjusting for the International Prognostic Index (IPI). The measurement of sFLC and ALC at diagnosis might be useful for the prognostic stratification of patients and sTLC measurement was of little prognostic utility in DLBCL.
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Histone demethylase jumonji AT-rich interactive domain 1B (JARID1B) controls mammary gland development by regulating key developmental and lineage specification genes.
J. Biol. Chem.
PUBLISHED: 05-06-2014
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The JmjC domain-containing H3K4 histone demethylase jumonji AT-rich interactive domain 1B (JARID1B) (also known as KDM5B and PLU1) is overexpressed in breast cancer and is a potential target for breast cancer treatment. To investigate the in vivo function of JARID1B, we developed Jarid1b(-/-) mice and characterized their phenotypes in detail. Unlike previously reported Jarid1b(-/-) strains, the majority of these Jarid1b(-/-) mice were viable beyond embryonic and neonatal stages. This allowed us to further examine phenotypes associated with the loss of JARID1B in pubertal development and pregnancy. These Jarid1b(-/-) mice exhibited decreased body weight, premature mortality, decreased female fertility, and delayed mammary gland development. Related to these phenotypes, JARID1B loss decreased serum estrogen level and reduced mammary epithelial cell proliferation in early puberty. In mammary epithelial cells, JARID1B loss diminished the expression of key regulators for mammary morphogenesis and luminal lineage specification, including FOXA1 and estrogen receptor ?. Mechanistically, JARID1B was required for GATA3 recruitment to the Foxa1 promoter to activate Foxa1 expression. These results indicate that JARID1B positively regulates mammary ductal development through both extrinsic and cell-autonomous mechanisms.
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Clinical features, survival and prognostic factors of primary testicular diffuse large B-cell lymphoma.
Chin. J. Cancer Res.
PUBLISHED: 04-24-2014
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To assess the clinical features, survival and prognostic factors of primary testicular diffuse large B-cell lymphoma (DLBCL).
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[Neuropad test for sudomotor function to predict the risk of diabetic foot ulceration].
Nan Fang Yi Ke Da Xue Xue Bao
PUBLISHED: 04-23-2014
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To assess the predictive value of Neuropad test on occurrence of diabetic foot ulceration (DFU) among type 2 diabetic patients.
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Long-Term Synaptic Plasticity in Rat Barrel Cortex.
Cereb. Cortex
PUBLISHED: 04-17-2014
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Rats generate sweeping whisker movements in order to explore their environments and identify objects. In somatosensory pathways, neuronal activity is modulated by the frequency of whisker vibration. However, the potential role of rhythmic neuronal activity in the cerebral processing of sensory signals and its mechanism remain unclear. Here, we showed that rhythmic vibrissal stimulation with short duration in anesthetized rats resulted in an increase or decrease in the amplitude of somatosensory-evoked potentials (SEPs) in the contralateral barrel cortex. The plastic change of the SEPs was frequency dependent and long lasting. The long-lasting enhancement of the vibrissa-to-cortex evoked response was side- but not barrel-specific. Local application of dl-2-amino-5-phosphonopentanoic acid into the barrel cortex revealed that this vibrissa-to-cortex long-term plasticity in adult rats was N-methyl-d-aspartate receptor-dependent. Most interestingly, whisker trimming through postnatal day (P)1-7 but not P29-35 impaired the long-term plasticity induced by 100 Hz vibrissal stimulation. The short period of rhythmic vibrissal stimulation did not induce long-lasting plasticity of field potentials in the thalamus. In conclusion, our results suggest that natural rhythmic whisker activity modifies sensory information processing in cerebral cortex, providing further insight into sensory perception.
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Approach to the study of flavone di-C-glycosides by high performance liquid chromatography-tandem ion trap mass spectrometry and its application to characterization of flavonoid composition in Viola yedoensis.
J Mass Spectrom
PUBLISHED: 03-20-2014
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The mass spectrometric (MS) analysis of flavone di-C-glycosides has been a difficult task due to pure standards being unavailable commercially and to that the reported relative intensities of some diagnostic ions varied with MS instruments. In this study, five flavone di-C-glycoside standards from Viola yedoensis have been systematically studied by high performance liquid chromatography-electrospray ionization-tandem ion trap mass spectrometry (HPLC-ESI-IT-MS(n) ) in the negative ion mode to analyze their fragmentation patterns. A new MS(2) and MS(3) hierarchical fragmentation for the identification of the sugar nature (hexoses or pentoses) at C-6 and C-8 is presented based on previously established rules of fragmentation. Here, for the first time, we report that the MS(2) and MS(3) structure-diagnostic fragments about the glycosylation types and positions are highly dependent on the configuration of the sugars at C-6 and C-8. The base peak ((0,2) X1 (0,2) X2 (-) ion) in MS(3) spectra of di-C-glycosides could be used as a diagnostic ion for flavone aglycones. These newly proposed fragmentation behaviors have been successfully applied to the characterization of flavone di-C-glycosides found in V. yedoensis. A total of 35 flavonoid glycosides, including 1 flavone mono-C-hexoside, 2 flavone 6,8-di-C-hexosides, 11 flavone 6,8-di-C-pentosides, 13 flavone 6,8-C-hexosyl-C-pentosides, 5 acetylated flavone C-glycosides and 3 flavonol O-glycosides, were identified or tentatively identified on the base of their UV profiles, MS and MS(n) (n?=?5) data, or by comparing with reference substances. Among these, the acetylated flavone C-glycosides were reported from V. yedoensis for the first time. Copyright © 2014 John Wiley & Sons, Ltd.
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Design, synthesis and biological evaluation of hydroxy- or methoxy-substituted 5-benzylidene(thio) barbiturates as novel tyrosinase inhibitors.
Bioorg. Med. Chem.
PUBLISHED: 03-20-2014
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Here a new class of hydroxy- or methoxy-substituted 5-benzylidene(thio)barbiturates were designed, synthesized and their inhibitory effects on the diphenolase activity of mushroom tyrosinase were evaluated. The results showed that several compounds had more potent tyrosinase inhibitory activities than the widely used tyrosinase inhibitor kojic acid (IC50=18.25?M). In particular, 3',4'-dihydroxylated 1e was found to be the most potent inhibitor with IC50 value of 1.52?M. The inhibition mechanism analysis revealed that the potential compounds 1e and 2e exhibited such inhibitory effects on tyrosinase by acting as the irreversible inhibitors. Structure-activity relationships' (SARs) analysis also suggested that further development of such compounds might be of interest.
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Phosphoprotein of human parainfluenza virus type 3 blocks autophagosome-lysosome fusion to increase virus production.
Cell Host Microbe
PUBLISHED: 03-03-2014
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Autophagy is a multistep process in which cytoplasmic components, including invading pathogens, are captured by autophagosomes that subsequently fuse with degradative lysosomes. Negative-strand RNA viruses, including paramyxoviruses, have been shown to alter autophagy, but the molecular mechanisms remain largely unknown. We demonstrate that human parainfluenza virus type 3 (HPIV3) induces incomplete autophagy by blocking autophagosome-lysosome fusion, resulting in increased virus production. The viral phosphoprotein (P) is necessary and sufficient to inhibition autophagosome degradation. P binds to SNAP29 and inhibits its interaction with syntaxin17, thereby preventing these two host SNARE proteins from mediating autophagosome-lysome fusion. Incomplete autophagy and resultant autophagosome accumulation increase extracellular viral production but do not affect viral protein synthesis. These findings highlight how viruses can block autophagosome degradation by disrupting the function of SNARE proteins.
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Inhibition of Kaposi's sarcoma-associated herpesvirus lytic replication by HIV-1 Nef and cellular microRNA hsa-miR-1258.
J. Virol.
PUBLISHED: 02-19-2014
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Kaposi's sarcoma-associated herpesvirus (KSHV) is causally linked to several AIDS-related malignancies, including Kaposi's sarcoma (KS), primary effusion lymphoma (PEL), and multicentric Castleman's disease. The interaction of human immunodeficiency virus type 1 (HIV-1) and KSHV has a central role in promoting the aggressive manifestations of AIDS-KS. We have previously shown that negative factor (Nef), a secreted HIV-1 protein, synergizes with KSHV viral interleukin-6 (vIL-6) to promote angiogenesis and tumorigenesis by activating the AKT pathway (X. Zhu, et al., Oncogene, 22 April 2013, http://dx.doi.org/10.1038/onc.2013.136). Here, we further demonstrated the role of soluble and ectopic Nef in the regulation of KSHV latency. We found that both soluble Nef protein and ectopic expression of Nef by transfection suppressed the expression of KSHV viral lytic mRNA transcripts and proteins and the production of infectious viral particles. MicroRNA (miRNA) microarray analysis identified a number of Nef-regulated miRNAs. Bioinformatics and luciferase reporter analyses showed that one of the Nef-upregulated miRNAs, cellular miRNA 1258 (hsa-miR-1258), directly targeted a seed sequence in the 3' untranslated region (UTR) of the mRNA encoding the major lytic switch protein (RTA), which controls KSHV reactivation from latency. Ectopic expression of hsa-miR-1258 impaired RTA synthesis and enhanced Nef-mediated inhibition of KSHV replication, whereas repression of hsa-miR-1258 has the opposite effect. Mutation of the seed sequence in the RTA 3'UTR abolished downregulation of RTA by hsa-miR-1258. Collectively, these novel findings demonstrate that, by regulating cellular miRNA, Nef may inhibit KSHV replication to promote viral latency and contribute to the pathogenesis of AIDS-related malignancies.
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Clinical severity of Gitelman syndrome determined by serum magnesium.
Am. J. Nephrol.
PUBLISHED: 02-17-2014
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Normomagnesemia is considered atypical in Gitelman syndrome (GS). Here, we describe clinical, pathological and genetic characteristics in Chinese GS patients with or without hypomagnesemia in order to determine whether serum magnesium concentration indicates the severity of the disease.
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Improved glomerular filtration rate estimation using new equations combined with standardized cystatin C and creatinine in Chinese adult chronic kidney disease patients.
Clin. Biochem.
PUBLISHED: 02-08-2014
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The newly developed glomerular filtration rate (GFR)-estimating equations developed by the CKD-EPI Collaboration and Feng et al. (2013) that are based on standardized serum cystatin C (ScysC), combined/not combined with serum creatinine (Scr), require further validation in China. We compared the performance of four new equations (CKD-EPIcys, CKD-EPIcr-cys, Fengcys, and Fengcr-cys equations) with the CKD-EPI creatinine equation (CKD-EPIcr) in adult Chinese chronic kidney disease (CKD) patients to clarify their clinical application.
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A phase I clinical trial assessing the safety and tolerability of combretastatin A4 phosphate injections.
Anticancer Drugs
PUBLISHED: 02-07-2014
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Combretastatin A4 phosphate (CA4P) is a prodrug that selectively destroys tumor blood vessels, and has shown efficacy as a targeted anticancer drug in both animal models and clinical trials. The aims of this single-center, open label, phase I clinical trial were to investigate the safety and tolerability of CA4P administered intravenously to patients aged 18-65 years with advanced solid tumors. Using a dose-escalation protocol, patients were assigned to five groups that received injections with 20 (n=3), 33 (n=3), 50 (n=11), 65 (n=6), or 85 (n=2) mg/m² CA4P. Patients in the 20 and 85 mg/m² groups received a single dose and the other groups received multiple doses. Adverse events (AE), cardiovascular parameters, and biochemical investigations were studied, and the maximum tolerated dose was determined. Of twenty-five patients enrolled, eight were withdrawn/excluded (not because of AE). There were no deaths. A total of 394 AE occurred in the 25 patients, with 89.3% considered related/possibly related to the drug. AE included headache and dizziness (19.8%), tumor-induced pain (14.2%), vascular vagal excitation (10.7%), and vomiting (9.4%). Ninety-five percent of AE were mild (grades 0-II), with only 5% being grade III-IV. Drug administration was associated with biphasic changes in heart rate and blood pressure, and only limited abnormalities in the laboratory investigations performed. The maximum tolerated dose was 65 mg/m². We conclude that CA4P is generally well tolerated, with the vast majority of AE that occurred being of mild severity. Further studies will establish the role of CA4P in cancer therapy.
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Significance of glioma-associated oncogene homolog 1 (GLI1) expression in claudin-low breast cancer and crosstalk with the nuclear factor kappa-light-chain-enhancer of activated B cells (NF¿B) pathway.
Breast Cancer Res.
PUBLISHED: 02-05-2014
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IntroductionThe recently identified claudin-low subtype of breast cancer is enriched for cells with stem-like and mesenchymal-like characteristics. This subtype is most often triple-negative (lacking the estrogen and progesterone receptors (ER, PR) as well as lacking epidermal growth factor 2 (HER2) amplification) and has a poor prognosis. There are few targeted treatment options available for patients with this highly aggressive type of cancer.MethodsUsing a high throughput inhibitor screen, we identified high expression of glioma-associated oncogene homolog 1 (GLI1), the effector molecule of the hedgehog (Hh) pathway, as a critical determinant of cell lines that have undergone an epithelial to mesenchymal transition (EMT).ResultsHigh GLI1 expression is a property of claudin-low cells and tumors and correlates with markers of EMT and breast cancer stem cells. Knockdown of GLI1 expression in claudin-low cell lines resulted in reduced cell viability, motility, clonogenicity, self-renewal, and reduced tumor growth of orthotopic xenografts. We observed non-canonical activation of GLI1 in claudin-low and EMT cell lines, and identified crosstalk with the NF¿B pathway.ConclusionsThis work highlights the importance of GLI1 in the maintenance of characteristics of metastatic breast cancer stem cells. Remarkably, treatment with an inhibitor of the NF¿B pathway reproducibly reduces GLI1 expression and protein levels. We further provide direct evidence for the binding of the NF¿B subunit p65 to the GLI1 promoter in both EMT and claudin-low cell lines. Our results uncover crosstalk between NF¿B and GLI1 signals and suggest that targeting these pathways may be effective against the claudin-low breast cancer subtype.
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Histone demethylase RBP2 is critical for breast cancer progression and metastasis.
Cell Rep
PUBLISHED: 02-03-2014
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Metastasis is a major clinical challenge for cancer treatment. Emerging evidence suggests that aberrant epigenetic modifications contribute significantly to tumor formation and progression. However, the drivers and roles of such epigenetic changes in tumor metastasis are still poorly understood. Using bioinformatic analysis of human breast cancer gene-expression data sets, we identified histone demethylase RBP2 as a putative mediator of metastatic progression. By using both human breast cancer cells and genetically engineered mice, we demonstrated that RBP2 is critical for breast cancer metastasis to the lung in multiple in vivo models. Mechanistically, RBP2 promotes metastasis as a pleiotropic positive regulator of many metastasis genes, including TNC. In addition, RBP2 loss suppresses tumor formation in MMTV-neu transgenic mice. These results suggest that therapeutic targeting of RBP2 is a potential strategy for inhibition of tumor progression and metastasis.
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Impact of psychological stress on irritable bowel syndrome.
World J. Gastroenterol.
PUBLISHED: 01-27-2014
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Psychological stress is an important factor for the development of irritable bowel syndrome (IBS). More and more clinical and experimental evidence showed that IBS is a combination of irritable bowel and irritable brain. In the present review we discuss the potential role of psychological stress in the pathogenesis of IBS and provide comprehensive approaches in clinical treatment. Evidence from clinical and experimental studies showed that psychological stresses have marked impact on intestinal sensitivity, motility, secretion and permeability, and the underlying mechanism has a close correlation with mucosal immune activation, alterations in central nervous system, peripheral neurons and gastrointestinal microbiota. Stress-induced alterations in neuro-endocrine-immune pathways acts on the gut-brain axis and microbiota-gut-brain axis, and cause symptom flare-ups or exaggeration in IBS. IBS is a stress-sensitive disorder, therefore, the treatment of IBS should focus on managing stress and stress-induced responses. Now, non-pharmacological approaches and pharmacological strategies that target on stress-related alterations, such as antidepressants, antipsychotics, miscellaneous agents, 5-HT synthesis inhibitors, selective 5-HT reuptake inhibitors, and specific 5-HT receptor antagonists or agonists have shown a critical role in IBS management. A integrative approach for IBS management is a necessary.
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TGF-?-induced upregulation of malat1 promotes bladder cancer metastasis by associating with suz12.
Clin. Cancer Res.
PUBLISHED: 01-21-2014
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TGF-? promotes tumor invasion and metastasis by inducing an epithelial-mesenchymal transition (EMT). However, the underlying mechanisms causing this are not entirely clear. Long noncoding RNAs (lncRNA) have been shown to play important regulatory roles in cancer progression. The lncRNA malat1 (metastasis associated lung adenocarcinoma transcript 1) is a critical regulator of the metastasis phenotype of lung cancer cells.
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Comparison of immunohistochemistry with fluorescence in situ hybridization in determining the human epidermal growth factor receptor 2 status of breast cancer specimens: a multicenter study of 3,149 Chinese patients.
Chin. Med. J.
PUBLISHED: 01-21-2014
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Accurate detection of human epidermal growth factor receptor 2 (HER2) expression and gene amplification is crucial for the application of HER2-specific therapy and for evaluating the response of patients with breast cancer. A uniform and standard procedure of immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) needs to be established for evaluating the HER2 status in breast cancer tissues for the treatment of patients with real HER2-positive tumors. The present multicenter study was aimed to examine the HER2 status in breast cancer specimens from Chinese patients using both IHC and FISH methods.
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Long non-coding RNA UCA1 increases chemoresistance of bladder cancer cells by regulating Wnt signaling.
FEBS J.
PUBLISHED: 01-20-2014
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Chemotherapy is a reasonable alternative to cystectomy in patients with invasive and advanced bladder cancer. However, bladder cancer cells often develop drug resistance to these therapies, and ~ 50% of patients with advanced bladder cancer do not respond to chemotherapy. Recent studies have shown that long non-coding RNA (lncRNA) is involved in the development of chemoresistance. Here we investigated the role of the urothelial cancer-associated 1 (UCA1) lncRNA in cisplatin resistance during chemotherapy for bladder cancer. We showed that cisplatin-based chemotherapy results in up-regulation of UCA1 expression in patients with bladder cancer. Similarly, UCA1 levels are increased in cisplatin-resistant bladder cancer cells. Over-expression of UCA1 significantly increases the cell viability during cisplatin treatment, whereas UCA1 knockdown reduces the cell viability during cisplatin treatment. UCA1 inhibition also partially overcomes drug resistance in cisplatin-resistant T24 cells. Furthermore, we showed that UCA1 positively regulates expression of wingless-type MMTV integration site family member 6 (Wnt6) in human bladder cancer cell lines. UCA1 and Wnt6 expression is also positively correlated in vivo. Up-regulation of UCA1 activates Wnt signaling in a Wnt6-dependent manner. We finally demonstrate that UCA1 increases the cisplatin resistance of bladder cancer cells by enhancing the expression of Wnt6, and thus represents a potential target to overcome chemoresistance in bladder cancer.
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Exendin-4 alleviates high glucose-induced rat mesangial cell dysfunction through the AMPK pathway.
Cell. Physiol. Biochem.
PUBLISHED: 01-13-2014
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Glucagon-like peptide-1 (GLP-1), which counteracts insulin resistance in humans with type 2 diabetes, has been shown to ameliorate diabetic nephropathy in experimental models. However, the mechanisms through which GLP-1 modulates renal function remained illdefined. The present study investigated the putative mechanisms underlying effects of exendin-4, a GLP-1 analog, on mesangial cell proliferation and fibronectin.
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Breast cancer cells are arrested at different phases of the cell cycle following the re-expression of ARHI.
Oncol. Rep.
PUBLISHED: 01-11-2014
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ARHI is a maternally imprinted tumor suppressor gene that is expressed in normal breast epithelial cells but not in most breast cancer cells. Aberrant methylation and hypernomic histone deacetylation have been implicated in the silencing of ARHI. To investigate the mechanism of ARHI induction, MDA-MB-231 breast cancer cells were either transfected with the eukaryotic expression vector, pcDNA3.1(+)-ARHI, or were simultaneously treated with a histone deacetylase inhibitor, [trichostatin A, (TSA)] and the methyltransferase inhibitor, 5-aza-2'-deoxycytidine (DAC). The latter treatment group also included the targeting of ARHI by small interfering RNA (siRNA) to further examine interactions between ARHI and the drugs applied. Levels of ARHI were detected by western blotting, MTT assays were used to evaluate cell proliferation, and both cell cycle progression and apoptosis were detected using flow cytometry. Both the transfection of pcDNA3.1(+)?ARHI and the application of TSA+DAC induced the expression of ARHI. Furthermore, reduced cell proliferation, cell cycle arrest and enhanced apoptosis were observed for both groups compared to controls. However, a G1/S cell cycle arrest was observed for the pcDNA3.1(+)-ARHI group, while a G2 cell cycle arrest was observed for the TSA+DAC group. The latter effect was reversed with the introduction of ARHI-targeted siRNA in combination with TSA+DAC treatment. To further clarify these observations, expression levels of several key cell cycle regulators were analyzed by western blotting. The pcDNA3.1(+)-ARHI group exhibited higher expression levels of p53, p21 and p27, and lower levels of cyclin D1, CDK4 and CDK6 when compared to the control group (P<0.05). For the TSA+DAC group, higher levels of p53, p21, cyclin B1 and Chk1 were detected, concomitant with lower levels of CDK1, when compared to the control group. Taken together, these results suggest that ARHI acts as a tumor suppressor gene in MDA-MB-231 cells and, although TSA+DAC can block the cells at different cell cycle phage, the antitumor effect is ARHI-dependent.
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Selective activation of cholinergic basal forebrain neurons induces immediate sleep-wake transitions.
Curr. Biol.
PUBLISHED: 01-11-2014
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The basal forebrain (BF) plays a crucial role in cortical activation [1, 2]. However, the exact role of cholinergic BF (ch-BF) neurons in the sleep-wake cycle remains unclear [3, 4]. We demonstrated that photostimulation of ch-BF neurons genetically targeted with channelrhodopsin 2 (ChR2) was sufficient to induce an immediate transition to waking or rapid eye movement (REM) sleep from slow-wave sleep (SWS). Light stimulation was most likely to induce behavioral arousal during SWS, but not during REM sleep, a result in contrast to the previously reported photostimulation of noradrenergic or hypocretin neurons that induces wake transitions from both SWS and REM sleep. Furthermore, the ratio of light-induced transitions from SWS to wakefulness or to REM sleep did not significantly differ from that of natural transitions, suggesting that activation of ch-BF neurons facilitates the transition from SWS but does not change the direction of the transition. Excitation of ch-BF neurons during wakefulness or REM sleep sustained the cortical activation. Stimulation of these neurons for 1 hr induced a delayed increase in the duration of wakefulness in the subsequent inactive period. Our results suggest that activation of ch-BF neurons alone is sufficient to suppress SWS and promote wakefulness and REM sleep.
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A XANES study of LiVPO4F: a factor analysis approach.
Phys Chem Chem Phys
PUBLISHED: 01-11-2014
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Evolving factor analysis (EFA) of X-ray absorption near-edge spectroscopy (XANES) data is shown to be a useful tool to understand the phase relationships and compositional ranges of stability in the LiVPO4F-VPO4F system. EFA was used to calculate the concentration of phases versus state-of-charge in a lithium-ion battery and true XANES spectra. The results of EFA showed that, indeed, three phases were present during cycling of a LiVPO4F?Li cell: LiVPO4F, LixVPO4F, and VPO4F. In contrast to what was reported by others, the second phase was not a fixed composition with x = 0.67, but, instead, existed over a range of lithium stoichiometry, x = 0.25 to 0.80. EFA results also showed that the reactions leading to these phases are reversible.
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B7-H6 expression in non-small cell lung cancers.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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B7 family has been known to be a negative regulator of immunity response in patients with lung cancer. B7-H6 as a novel identified member of B7 family is found to trigger natural killer (NK) cell cytotoxicity and cytokine secretion by binding natural cytotoxicity receptor NKp30. Up until now, no investigations have been made about B7-H6 expression in lung cancer. We present the result of the B7-H6 prognostic value in 65 non-small cell lung cancer (NSCLC) tissues and 65 matched adjacent non-tumor tissues by Immunohistochemistry (IHC). Meanwhile, fluorescence activated cell sorter (FACS) analysis was used to detect B7-H6 receptor NKp30 expression in 7 non-small cell lung cancer tissues and 7 adjacent non-tumor tissues. Here, the result showed B7-H6 immunoreactivity in 6/65 (9.23%) lung cancer patients and 4/65 (6.15%) in adjacent non-tumor tissues. No relationship was found between B7-H6 expression and clinic pathological features. Similarly, no relevance was found for NKp30 expression in lung cancer tissues and non-tumor tissues. However, B7-H6 positive carcinomas were significantly correlated with degree of differentiation (P = 0.044). Three year survival rate after operation did not show the prognostic value for B7-H6 expression. Our study suggests that B7-H6 has a limited value as a prognostic marker in the patients of lung cancer.
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EF-G and EF4: translocation and back-translocation on the bacterial ribosome.
Nat. Rev. Microbiol.
PUBLISHED: 12-23-2013
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Ribosomes translate the codon sequence of an mRNA into the amino acid sequence of the corresponding protein. One of the most crucial events is the translocation reaction, which involves movement of both the mRNA and the attached tRNAs by one codon length and is catalysed by the GTPase elongation factor G (EF-G). Interestingly, recent studies have identified a structurally related GTPase, EF4, that catalyses movement of the tRNA2-mRNA complex in the opposite direction when the ribosome stalls, which is known as back-translocation. In this Review, we describe recent insights into the mechanistic basis of both translocation and back-translocation.
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A statistical model for QTL mapping in polysomic autotetraploids underlying double reduction.
Brief. Bioinformatics
PUBLISHED: 10-30-2013
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As a group of economically important species, linkage mapping of polysomic autotetraploids, including potato, sugarcane and rose, is difficult to conduct due to their unique meiotic property of double reduction that allows sister chromatids to enter into the same gamete. We describe and assess a statistical model for mapping quantitative trait loci (QTLs) in polysomic autotetraploids. The model incorporates double reduction, built in the mixture model-based framework and implemented with the expectation-maximization algorithm. It allows the simultaneous estimation of QTL positions, QTL effects and the degree of double reduction as well as the assessment of the estimation precision of these parameters. We performed computer simulation to examine the statistical properties of the method and validate its use through analyzing real data in tetraploid switchgrass.
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[The roles of glutamate in sleep and wakefulness].
Zhejiang Da Xue Xue Bao Yi Xue Ban
PUBLISHED: 10-30-2013
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Glutamate as an excitatory neurotransmitter in the central nervous system, participate in initiation and maintaining of sleep and wakefulness. The paper presents an overview of the research progress of glutamate in the regulation of sleep and wakefulness, especially focuses on its role in the brainstem, lateral hypothalamus and basal forebrain. Glutamate in the brain stem regulates the brain activity and maintains muscle tone during the wakefulness, as well as adjusts the electroencephalograph (EEG) in rapid eye movement phase and leads to muscle weakness. Glutamate in the lateral hypothalamus participates in the lateral hypothalamic arousal system by activating orexins neurons. The basal forebrain glutamatergic neurons take part in EEG synchronization and cause the decrease of sleep. Finally,The glutamatergic neurons of the cerebral cortex is not just a target of the arousal system, but itself contribute to regulation of arousal. Meantime, the glutamatergic neurons can regulate sleep stages through interaction with other types of neurons, which forms a complex sleep-wake regulation network in the brain. These indicate that the switches between different phases of sleep and wakefulness have different neuronal circuits.So we also reviewed the neuronal circuits and mechanisms that glutamate may be involved in. This review will help us to get a better understanding of the roles of glutamate in sleep and wakefulness.
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MicroRNA-361-5p facilitates cervical cancer progression through mediation of epithelial-to-mesenchymal transition.
Med. Oncol.
PUBLISHED: 09-19-2013
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The epithelial-to-mesenchymal transition (EMT) promotes cervical cancer progression, and microRNAs have been found to be master regulators of EMT. The aim of the present study was to investigate the functional roles of miR-361-5p in EMT and cervical cancer progression. Differentially expressed miRNAs were screened with microarray analysis in SiHa and CasKi cells; cellular and animal studies were used to observe the impact of miR-361-5p on cell proliferation; invasion and migration ability of cervical cancer cells were investigated by Transwell and wound-healing studies; enzyme-linked immunosorbent assay and Western blot methods were used to test protein levels; miR-361-5p level in cervical cancer specimens was detected with in situ hybridization. MicroRNA-361-5p (miR-361-5p) was found to be the most upregulated microRNA in transferred cervical cancer cells. MiR-361-5p acts as an oncogene to enhance cell proliferation and promote cell invasion, and these changes were accompanied by the characteristics of EMT. miR-361-5p is increasingly elevated during cervical carcinoma progression and inversely correlated with E-cadherin, a marker of EMT. These findings suggest that miR-361-5p is an oncomicroRNA and an important factor in the progression of cervical cancer.
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A new tetrahydrofuran lignan diglycoside from Viola tianshanica Maxim.
Molecules
PUBLISHED: 09-11-2013
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A new lignan glycoside, tianshanoside A (1), together with a known phenylpropanoid glycoside, syringin (2) and two known lignan glycosides, picraquassioside C (3), and aketrilignoside B (4), were isolated from the whole plant of Viola tianshanica Maxim. The structure of the new compound was elucidated by extensive NMR (1H, 13C, COSY, HSQC, HMBC and ROESY) and high resolution mass spectrometry analysis. The three lignans 1, 3, and 4 did not exhibit significant cytotoxicity against human gastric cancer Ags cells or HepG2 liver cancer cells. This is the first report of the isolation of a lignan skeleton from the genus Viola L.
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An amino acid of human parainfluenza virus type 3 nucleoprotein is critical for template function and cytoplasmic inclusion body formation.
J. Virol.
PUBLISHED: 09-11-2013
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The nucleoprotein (N) and phosphoprotein (P) interaction of nonsegmented negative-strand RNA viruses is essential for viral replication; this includes N?-P (N?, free of RNA) interaction and the interaction of N-RNA with P. The precise site(s) within N that mediates the N-P interaction and the detailed regulating mechanism, however, are less clear. Using a human parainfluenza virus type 3 (HPIV3) minigenome assay, we found that an N mutant (N(L478A) did not support reporter gene expression. Using in vivo and in vitro coimmunoprecipitation, we found that N(L478A) maintains the ability to form N(L478A)?-P, to self-assemble, and to form N(L478A)-RNA but that N(L478A)-RNA does not interact with P. Using an immunofluorescence assay, we found that N-P interaction provides the minimal requirement for the formation of cytoplasmic inclusion bodies, which contain viral RNA, N, P, and polymerase in HPIV3-infected cells. N(L478A) was unable to form inclusion bodies when coexpressed with P, but the presence of N rescued the ability of N(L478A) to form inclusion bodies and the transcriptional function of N(L478A), thereby suggesting that hetero-oligomers formed by N and N(L478A) are functional and competent to form inclusion bodies. Furthermore, we found that N(L478A) is also defective in virus growth. To our knowledge, we are the first to use a paramyxovirus to identify a precise amino acid within N that is critical for N-RNA and P interaction but not for N(0)-P interaction for the formation of inclusion bodies, which appear to be bona fide sites of RNA synthesis.
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Direct comparison of a genetically encoded sensor and small molecule indicator: implications for quantification of cytosolic Zn(2+).
ACS Chem. Biol.
PUBLISHED: 09-03-2013
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Fluorescent sensors are powerful tools for visualizing and quantifying molecules and ions in living cells. A variety of small molecule and genetically encoded sensors have been developed for studying intracellular Zn(2+) homeostasis and signaling, but no direct comparisons exist, making it challenging for researchers to identify the appropriate sensor for a given application. Here we directly compare the widely used small molecule probe FluoZin-3 and a genetically encoded sensor, ZapCY2. We demonstrate that, in contrast to FluoZin-3, ZapCY2 exhibits a well-defined cytosolic localization, provides estimates of Zn(2+) concentration with little variability, does not perturb cytosolic Zn(2+) levels, and exhibits rapid Zn(2+) response dynamics. ZapCY2 was used to measure Zn(2+) concentrations in 5 different cell types, revealing higher cytosolic Zn(2+) levels in prostate cancer cells compared to normal prostate cells (although the total zinc is reduced in prostate cancer cells), suggesting distinct regulatory mechanisms.
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Pharmacokinetics, tissue distribution and excretion study of dictamnine, a major bioactive component from the root bark of Dictamnus dasycarpus Turcz. (Rutaceae).
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 08-22-2013
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Dictamnine is an herbal ingredient isolated from the root bark of Dictamnus dasycarpus Turcz. (Rutaceae). The present study was aimed at the development of an ultra-high performance liquid chromatography-tandem mass spectrometry method to quantify the concentration of dictamnine in rat plasma and tissues for the in vivo pharmacokinetics, tissue distribution and excretion study. Biological samples were processed with protein precipitation. Skimmianine was chosen as internal standard. The chromatographic separation was carried out on a Thermo Syncronis C18 column (2.1mm×50mm, 1.7?m) with an isocratic mobile phase consisting of methanol and 0.1% formic acid water (75:25, v/v). The detection was accomplished by using positive ion electrospray ionization in multiple reaction monitoring (MRM) mode. The MS/MS ion transitions were monitored at m/z 200.0?129.0 for dictamnine and 260.3?227.1 for IS, respectively. An excellent linearity was observed over the concentration range from 0.5 to 250ng/mL. The lower limit of quantification (LLOQ) was 0.5ng/mL for dictamnine. The developed method was rapid, accurate, and highly sensitive and selective. It was successfully applied to the in vivo pharmacokinetics, tissue distribution and excretion study of dictamnine in rats after oral or intravenous administration of dictamnine.
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Astrocyte-restricted disruption of connexin-43 impairs neuronal plasticity in mouse barrel cortex.
Eur. J. Neurosci.
PUBLISHED: 07-26-2013
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There is intensive gap-junctional coupling between glial processes, but their significance in sensory functions remains unknown. Connexin-43 (Cx43), a major component of astrocytic gap-junction channels, is abundantly expressed in astrocytes. To investigate the role of Cx43-mediated gap junctions between astrocytes in sensory functions, we generated Cx43 knockout (KO) mice with a mouse line carrying loxP sites flanking exon 2 of the Cx43 gene and the transgenic line expressing Cre recombinase under control of the glial fibrillary acidic protein promoter, which exhibited a significant loss of Cx43 in astrocytes in the barrel cortex. Although Cx43 expression between the astrocytes measured by immunohistochemistry was virtually abolished in Cx43 KO mice, they had normal architecture in the barrel cortex but the intensity of cytochrome oxide histochemistry decreased significantly. In vivo electrophysiological analysis revealed that the long-term potentiation of the vibrissal evoked responses in the barrel cortex evoked by high-frequency rhythmic vibrissal stimuli (100 Hz, 1 s) was abolished in Cx43 KO mice. Current source density analysis also revealed that astrocytic Cx43 was important to the flow of excitation within the laminar connections in barrel cortex. Behavioral tests showed that the ability of Cx43 KO mice to sense the environment with their whiskers decreased. Even so, the jump-stand experiment showed that they could still discriminate rough from smooth surfaces. Our findings suggest that Cx43-mediated gap-junctional coupling between astrocytes is important in the neuron-glia interactions required for whisker-related sensory functions and plasticity.
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Ghrelin contributes to protection of hepatocellular injury induced by ischaemia/reperfusion.
Liver Int.
PUBLISHED: 07-24-2013
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Ghrelin, a gut hormone with pleiotropic effects, may act as a protective signal in parenchymal cells. We investigated the protective effects of ghrelin on hepatocytes after ischaemia/reperfusion (I/R).
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Simplified protocol for isolation of multipotential NG2 cells from postnatal mouse.
J. Neurosci. Methods
PUBLISHED: 07-10-2013
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The functions of NG2 cells have attracted much attention since they were identified. At present, our understanding of their properties and functions is still limited due to the lack of an easy protocol for isolating them from mice.
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The complete mitogenome of the Chinese swamp shrimp Neocaridina denticulata sinensis Kemp 1918 (Crustacea: Decapoda: Atyidae).
Mitochondrial DNA
PUBLISHED: 06-24-2013
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Abstract In this study we determined the complete mitochondrial genome (mitogenome) of the Chinese swamp shrimp Neocaridina denticulata sinensis Kemp, 1918 (Decapoda, Atyidae). The mitogenome consists of 15,561?bp encoding 37 genes that are involved in mitochondrial protein synthesis as well as respiration chain/oxidative phosphorylation. Besides, a 672-bp putative control region was identified between the small subunit ribosomal RNA and tRNA-Ile genes, the size and AT content of which is moderate within the Decapoda. The gene arrangement of the mitogeonme follows the pancrustacean ancestral pattern shared by the decapod subfamily Dendrobranchiata, pleocyematan infrafamilies Caridea and Palinura. Our results will provide important data for various levels of phylogeny and further evolution.
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The complete mitogenome of the lined shore crab Pachygrapsus crassipes Randall 1840 (Crustacea: Decapoda: Grapsidae).
Mitochondrial DNA
PUBLISHED: 06-24-2013
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Abstract In this study we sequenced and analyzed the complete mitochondrial genome (mitogenome) of the lined shore crab Pachygrapsus crassipes Randall, 1840 (Crustacea: Grapsidae). The full-length P. crassipes mitogenome is 15,652?bp in size, which encodes the same 37 genes as all metazoan mitogenomes. Both AT contents of the entire molecule as well as putative control region display lowest values among all mitogenomes of the brachyuran crabs determined to date. The mitochondrial gene order follows a classic crab-type arrangement that underwent a unique tRNA translocation from the pancrustacean ancestral pattern. Our results will provide important data for phylogenetic as well as biogeographic studies.
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High-dose therapy and autologous stem cell transplantation in peripheral T-cell lymphoma: treatment outcome and prognostic factor analysis.
Int. J. Hematol.
PUBLISHED: 06-11-2013
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Peripheral T-cell lymphoma (PTCL) carries a poor prognosis with conventional treatment. We retrospectively analyzed data from 45 patients with PTCL who received high-dose therapy and autologous stem cell transplantation (HDT/ASCT) from 1990 to 2008 in our center. Eighteen patients underwent HDT/ASCT in complete remission to induction chemotherapy (CR1), and 27 patients underwent HDT/ASCT in other disease statuses. The median follow-up was 113.5 months (range 52.6-261.0) for surviving patients. The 5-year overall survival (OS) and progression-free survival (PFS) were 64 and 60 %, respectively. The 5-year OS for patients in CR1 and in other disease statuses was 89 and 47 %, respectively (P = 0.002), and 5-year PFS was 83 and 43 % (P = 0.007). In the subgroup excluding anaplastic large cell lymphoma, patients transplanted in CR1 also had significantly better 5-year OS (82 vs. 37 %, P = 0.009) and PFS (82 vs. 33 %, P = 0.008) than those transplanted in other disease statuses. Multivariate analysis showed that CR1 status was the only significant prognostic factor for OS (P = 0.040) and PFS (P = 0.040). These results support the use of HDT/ASCT consolidation in CR1 for PTCL patients. Prospective randomized trials are necessary to confirm the efficacy of this approach.
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Histone demethylase RBP2 promotes lung tumorigenesis and cancer metastasis.
Cancer Res.
PUBLISHED: 05-30-2013
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The retinoblastoma binding protein RBP2 (KDM5A) is a histone demethylase that promotes gastric cancer cell growth and is enriched in drug-resistant lung cancer cells. In tumor-prone mice lacking the tumor suppressor gene RB or MEN1, genetic ablation of RBP2 can suppress tumor initiation, but the pathogenic breadth and mechanistic aspects of this effect relative to human tumors have not been defined. Here, we approached this question in the context of lung cancer. RBP2 was overexpressed in human lung cancer tissues where its depletion impaired cell proliferation, motility, migration, invasion, and metastasis. RBP2 oncogenicity relied on its demethylase and DNA-binding activities. RBP2 upregulated expression of cyclins D1 and E1 while suppressing the expression of cyclin-dependent kinase inhibitor p27 (CDKN1B), each contributing to RBP2-mediated cell proliferation. Expression microarray analyses revealed that RBP2 promoted expression of integrin-?1 (ITGB1), which is implicated in lung cancer metastasis. Mechanistic investigations established that RBP2 bound directly to the p27, cyclin D1, and ITGB1 promoters and that exogenous expression of cyclin D1, cyclin E1, or ITGB1 was sufficient to rescue proliferation or migration/invasion, respectively. Taken together, our results establish an oncogenic role for RBP2 in lung tumorigenesis and progression and uncover novel RBP2 targets mediating this role.
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Prolonged pruritic rash following influenza A (H1N1) vaccination.
Singapore Med J
PUBLISHED: 05-30-2013
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In Singapore, the approved influenza A (H1N1) vaccines are Panvax® and Pandemrix®. An estimated 425,000 doses of Panvax and less than 100 doses of Pandemrix had been distributed in Singapore from November 2009 to February 2010. Reviews on the H1N1 vaccine have concluded that it has a safety profile similar to that of seasonal influenza vaccines. From the time the H1N1 vaccination was implemented in Singapore on November 3, 2009, up to October 11, 2010, the Health Sciences Authority had received 173 adverse event reports from healthcare professionals. We report a case of prolonged illness after H1N1 vaccination.
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[Rapid determination of six preservative residues in fruits and vegetables by high performance liquid chromatography using dispersive solid phase extraction].
Se Pu
PUBLISHED: 05-24-2013
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A dispersive solid phase extraction-high performance liquid chromatographic (HPLC) method was established for the simultaneous determination of 2,4-D, thiabendazole, 2-naphthol, o-phenyl phenol, diphenyl ether and biphenyl in the fruits and vegetables. The samples were vortexed for extraction with acetonitrile containing sodium chloride and anhydrous magnesium sulfate. The acetonitrile extraction was purified by acidic alumina dispersed solid phase extraction. The analysis was performed on an Agilent TC C18 column (250 mm x 4.6 mm, 5 microm) and an ultraviolet detector at 235 nm with a mobile phase of methanol-0.02 mol/L (pH 6) potassium dihydrogen phosphate solution, at a flow rate of 1.0 mL/min with gradient elution. Good linearities were observed in the range of 0.5-20 mg/L with correlation coefficients greater than 0.99. The average recoveries of the six preservatives in fruits and vegetables were in the range of 84.2% -99. 1% at three spiked levels of 1, 2 and 10 mg/kg (n = 6) and the relative standard deviations (RSDs) were in the range of 1.67%-10.3%. The limits of quantification were 1 mg/kg. This method is simple, accurate and suitable for the determination of the six preservatives in fruits and vegetables.
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A new method for Schwann-like cell differentiation of adipose derived stem cells.
Neurosci. Lett.
PUBLISHED: 05-16-2013
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Peripheral nerve repair can be enhanced by Schwann cell transplantation, but the clinical application of this procedure is limited by donor site morbidity and the inability to quickly generate a sufficient number of cells. Thus, alternative cell systems for the generation of Schwann cells are desired. Schwann-like cell induced from adipose-derived stem cells (ADSCs) may be one of the ideal alternative cell systems for Schwann cell generation. Although co-culture with Schwann cells or chemicals combined with a mixture of glial growth factors are often utilized for Schwann cell-like differentiation of ADSCs, these methods are usually complicated or expensive. In this experiment, the rat sciatic nerve was cut, and then soaked in culture medium for two days. The treated culture medium was used as an induction agent after filtering. The obtained ADSCs were incubated with the above induction culture medium for five days. Then, expression of the typical Schwann cell markers, S-100 and GFAP proteins was determined by immunocytochemical staining and Western blotting. The results showed that almost all of the treated ADSCs displayed a spindle shape like morphology after being incubated with induction culture medium for 24h and expressed S-100 and GFAP proteins after five days. All of these characteristics of differentiated rat ADSCs were similar to genuine Schwann cells. Thus, this new method, which utilized trophic factors secreted from sciatic nerve leachate, was capable of inducing ADSC differentiation into Schwann-like cell.
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The paradox of elongation factor 4: highly conserved, yet of no physiological significance?
Biochem. J.
PUBLISHED: 05-14-2013
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LepA [EF4 (elongation factor 4)] is a highly conserved protein found in nearly all known genomes. EF4 triggers back-translocation of the elongating ribosome, causing the translation machinery to move one codon backwards along the mRNA. Knockout of the corresponding gene in various bacteria results in different phenotypes; however, the physiological function of the factor in vivo is unclear. Although functional research on Guf1 (GTPase of unknown function 1), the eukaryotic homologue of EF4, showed that it plays a critical role under suboptimal translation conditions in vivo, its detailed mechanism has yet to be identified. In the present review we briefly cover recent advances in our understanding of EF4, including in vitro structural and biochemical studies, and research on its physiological role in vivo. Lastly, we present a hypothesis for back-translocation and discuss the directions future EF4 research should focus on.
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Considering CYP1A2 phenotype and genotype for optimizing the dose of olanzapine in the management of schizophrenia.
Expert Opin Drug Metab Toxicol
PUBLISHED: 05-04-2013
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Schizophrenia, a mental disorder, is a debilitating condition which typically strikes young people in their early 20s. Antipsychotic medications are widely prescribed for the treatment of schizophrenia however a balancing act is necessary to provide the correct dose to each patient. It is suggested that a large number of patients discontinue antipsychotic pharmacotherapy because the treatments provided do not always reduce the positive symptoms of the disease, while many have adverse effects on the patients. This implies that neither the incorrect drug nor the optimal dosage for that patient is achieved.
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Histone demethylases set the stage for cancer metastasis.
Sci Signal
PUBLISHED: 05-02-2013
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Metastasis is the major cause of cancer-related mortality. It is increasingly evident that epigenetic alterations in tumor cells enable them to overcome various barriers in this multistage process of cell spreading, and insight into the molecular roles of epigenetic regulators in tumor metastasis are just beginning to emerge. Histone demethylases appear to have critical roles in creating suitable epigenetic states for tumor cells to gain metastatic potential. These studies shed light on the roles of histone demethylases in tumor metastasis and highlight the importance of targeting these enzymes to suppress metastatic disease.
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CpG island hypermethylation-associated silencing of microRNAs promotes human endometrial cancer.
Cancer Cell Int.
PUBLISHED: 04-27-2013
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Endometrial cancer (EC) is the most common gynecologic malignancy, but the molecular events involved in the development and progression of EC remain unclear. This study aimed to explore epigenetic modification of genes and miRNAs involved in EC development.
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Preparation and application of polyclonal antibodiesagainst KSHV v-cyclin.
J Biomed Res
PUBLISHED: 04-20-2013
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We prepared rabbit polyclonal antibodies against Kaposis sarcoma-associated herpesvirus (KSHV)-encoded v-cyclin (ORF 72) and detected the natural viral protein using these polyclonal antibodies. Three antigenic polypeptides of v-cyclin were designed and synthesized. A fragment of the v-cyclin gene was cloned into a eukaryotic expression vector pEF-MCS-Flag-IRES/Puro to construct a recombinant vector, pEF v-cyclin. Then, pEF v-cyclin was transfected into 293T and EA.hy926 cells to obtain v-cyclin-Flag fusion proteins. Six New Zealand white rabbits were immunized with KLH-conjugated peptides to generate polyclonal antibodies against v-cyclin. The polyclonal antibodies were then characterized by ELISA and Western blotting assays. Finally, the polyclonal antibodies against v-cyclin were used to detect natural viral protein expressed in BCBL-1, BC-3, and JSC-1 cells. The results showed that using the Flag antibody, v-cyclin-Flag fusion protein was detected in 293T and EA.hy926 cells transfected with pEF-v-cyclin. Furthermore, ELISA showed that the titer of the induced polyclonal rabbit anti-v-cyclin antibodies was higher than 1:8,000. In Western blotting assays, the antibodies reacted specifically with the v-cyclin-Flag fusion protein as well as the natural viral protein. The recombinant expression vector pEF-v-cyclin was constructed successfully, and the polyclonal antibodies prepared can be used for various biological tests including ELISA and Western blotting assays.
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Prioritization of disease susceptibility genes using LSM/SVD.
IEEE Trans Biomed Eng
PUBLISHED: 04-18-2013
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Understanding the role of genetics in diseases is one of the most important tasks in the post-genome era. It is generally too expensive and time-consuming to perform experimental validation for all candidate genes related to disease. Computational methods play important roles for prioritizing these candidates. Herein, we propose an approach to prioritize disease genes using latent semantic mapping (LSM) based on singular value decomposition (SVD). Our hypothesis is that similar functional genes are likely to cause similar diseases. Measuring the functional similarity between known disease susceptibility genes and unknown genes is to predict new disease susceptibility genes. Taking autism as an instance, the analysis results of the top 10 genes prioritized demonstrate they might be autism susceptibility genes, which also indicates our approach could discover new disease susceptibility genes. The novel approach of disease gene prioritization could discover new disease susceptibility genes, and latent disease-gene relations. The prioritized results could also support the interpretive diversity and experimental views as computational evidence for disease researchers.
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Host gene expression profiling and in vivo cytokine studies to characterize the role of linezolid and vancomycin in methicillin-resistant Staphylococcus aureus (MRSA) murine sepsis model.
PLoS ONE
PUBLISHED: 02-26-2013
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Linezolid (L), a potent antibiotic for Methicillin Resistant Staphylococcus aureus (MRSA), inhibits bacterial protein synthesis. By contrast, vancomycin (V) is a cell wall active agent. Here, we used a murine sepsis model to test the hypothesis that L treatment is associated with differences in bacterial and host characteristics as compared to V. Mice were injected with S. aureus USA300, and then intravenously treated with 25 mg/kg of either L or V at 2 hours post infection (hpi). In vivo alpha-hemolysin production was reduced in both L and V-treated mice compared to untreated mice but the reduction did not reach the statistical significance [P?=?0.12 for L; P?=?0.70 for V). PVL was significantly reduced in L-treated mice compared to untreated mice (P?=?0.02). However the reduction of in vivo PVL did not reach the statistical significance in V- treated mice compared to untreated mice (P?=?0.27). Both antibiotics significantly reduced IL-1? production [P?=?0.001 for L; P?=?0.006 for V]. IL-6 was significantly reduced with L but not V antibiotic treatment [P<0.001 for L; P?=?0.11 for V]. Neither treatment significantly reduced production of TNF-?. Whole-blood gene expression profiling showed no significant effect of L and V on uninfected mice. In S. aureus-infected mice, L altered the expression of a greater number of genes than V (95 vs. 42; P?=?0.001). Pathway analysis for the differentially expressed genes identified toll-like receptor signaling pathway to be common to each S. aureus-infected comparison. Expression of immunomodulatory genes like Cxcl9, Cxcl10, Il1r2, Cd14 and Nfkbia was different among the treatment groups. Glycerolipid metabolism pathway was uniquely associated with L treatment in S. aureus infection. This study demonstrates that, as compared to V, treatment with L is associated with reduced levels of toxin production, differences in host inflammatory response, and distinct host gene expression characteristics in MRSA sepsis.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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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.