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Lv R, Wu L, Jin L, Lu Q, Wang M, Qu Y, Liu H. Depression, anxiety and quality of life in parents of children with epilepsy. Acta Neurol Scand 2009; 120:335-41. [PMID: 19456304 DOI: 10.1111/j.1600-0404.2009.01184.x] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVES To assess the impact of childhood epilepsy on parental quality of life (QOL) and psychological health, and to investigate possible correlations between parental QOL and background variables as well as parental anxiety and depression. SUBJECTS AND METHODS Parents having an epileptic child (n = 263) and parents having a healthy child (n = 270) were enrolled. Groups were in balance for background variables. Short-Form Health Survey (SF-36) Questionnaire, Zung Depression Scale (ZDS) and Zung Anxiety Scale (ZAS) were applied to all parents. Patients were divided into the first visit group (newly diagnosed epilepsy) and follow-up visit group. RESULTS The parents of children with epilepsy had significantly lower QOL scores in SF-36 for all subscales and higher levels of depression and anxiety by using ZDS and ZAS. The factors correlated with parental QOL were seizure control, visit status, anxiety, depression, employment, cost of epilepsy, status epilepticus, drug side effect and age of parents. CONCLUSIONS Childhood epilepsy has a severe impact on parental QOL and psychological health, and recognition of possible correlations between parental QOL and background variables will be helpful to improve parental QOL.
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Wang Z, Li W, Zhi D, Gao Q, Qu Y, Wang B. Prematurely condensed chromosome fragments in human lymphocytes induced by high doses of high-linear-energy-transfer irradiation. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2009; 679:9-12. [DOI: 10.1016/j.mrgentox.2009.08.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2009] [Revised: 07/04/2009] [Accepted: 08/01/2009] [Indexed: 10/20/2022]
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Gao H, Zhou J, Dai D, Qu Y. Photocatalytic Activity and Electronic Structure Analysis of N-doped Anatase TiO2: A Combined Experimental and Theoretical Study. Chem Eng Technol 2009. [DOI: 10.1002/ceat.200800624] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Ray PS, Wang J, Qu Y, Shin-Sim M, Shamonki J, Liu B, Hoon DS, Giuliano AE, Cui X. Role of FOXC1 in regulation of basal-like/triple-negative breast cancer. J Clin Oncol 2009. [DOI: 10.1200/jco.2009.27.15_suppl.11016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
11016 Background: Class identification studies have proposed 3 prognostically relevant molecular subtypes of breast cancer: luminal, HER2 and basal-like. The latter is associated with poor prognosis but its molecular basis is not clear. We hypothesized a direct correlation between FOXC1 expression and basal-like breast cancer. Methods: Expression of FOXC1, CK5, CK14, EGFR, c-Kit, αB-crystallin, ITGB4 and FOXC2 in basal-like breast cancer was examined using publicly available microarray datasets. A molecular signature of 40 genes sharing co-ordinate up or down regulation with FOXC1 was identified on one microarray (49 patients) and validated on 5 other microarrays (1,232 patients). The clinical significance of FOXC1 gene expression and the FOXC1 gene signature was evaluated using censored survival data. FOXC1 protein expression was assessed by immunohistochemistry (IHC) of a 96-sample breast cancer tissue microarray. Normal breast epithelial, luminal and basal breast cancer cells transfected with FOXC1 vectors were evaluated for cell proliferation, migration and invasion. Results: FOXC1 was found to be consistently and exclusively upregulated in basal-like triple negative breast cancer and was associated with poor overall survival (p<0.0001). The FOXC1 gene signature accurately predicted the basal-like phenotype. IHC analysis of FOXC1 protein expression in human breast cancers confirmed its potential to be used as a clinical biomarker of basal-like breast cancer. Normal breast epithelial cells and luminal breast cancer cells with low or no FOXC1 expression underwent epithelial-to-mesenchymal transition and displayed increased cellular proliferation, migration, invasion, and expression of basal cell markers when FOXC1 was overexpressed. In contrast, knockdown of FOXC1 by shRNA in basal-like breast cancer cells conferred luminal phenotype. Breast cancer progression-linked signaling pathways like NF-κB and p38MAPK were significantly stimulated in basal-like breast cancer as well as by in vitro FOXC1 overexpression. Conclusions: FOXC1 is a dominant determinant of the basal-like phenotype of breast cancer. We propose FOXC1 to be the single best molecular marker of and a potential therapeutic target for basal-like / triple negative breast cancer. No significant financial relationships to disclose.
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Qu Y, Zhang L, Mao M, Zhao F, Huang X, Yang C, Xiong Y, Mu D. Effects of DNAzymes targeting Aurora kinase A on the growth of human prostate cancer. Cancer Gene Ther 2008; 15:517-25. [PMID: 18404163 DOI: 10.1038/cgt.2008.22] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Aurora kinase A has been demonstrated to be involved in the malignant progression of many types of cancer including prostate cancer, we therefore hypothesized that Aurora kinase A might work as a valuable target for prostate cancer treatment. To test this hypothesis, we used DNAzyme technology to inhibit Aurora kinase A expression and evaluated the effects of DNAzymes as therapeutic agents to treat prostate cancer. In an in vitro cleavage assay, we found that a DNAzyme (DZ2) targeting Aurora kinase A could effectively cleave Aurora kinase A mRNA. When transfected into the prostate cancer cell line PC3, DZ2 was found to strongly inhibit the expression of Aurora kinase A examined by western blot analysis, and thus suppressed cell growth, arrested the progression of cell cycle, induced cell apoptosis and attenuated cell migration, as measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium assay, flow cytometry and Boyden chamber assay. Through in vivo study, we also found that DZ2 could significantly inhibit the growth of human prostate cancer xenografts in nude mice. In conclusion, DZ2 could effectively attenuate malignant progression of prostate cancer both in vitro and in vivo, suggesting that DNAzyme targeting Aurora kinase A may be used as a valuable therapy to treat prostate cancer.
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Chahine M, Qu Y, Mancarella S, Boutjdir M. Protein kinase C activation inhibits alpha1D L-type Ca channel: a single-channel analysis. Pflugers Arch 2007; 455:913-9. [PMID: 17909852 DOI: 10.1007/s00424-007-0342-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2007] [Revised: 08/24/2007] [Accepted: 09/05/2007] [Indexed: 10/22/2022]
Abstract
The recently reported alpha1D Ca channel in the heart is known to be regulated by protein kinase C (PKC) at the whole cell level and has been implicated in atrial fibrillation. The biophysical basis of this regulation at the single-channel level is not known. Therefore, the effect of PKC activation was studied on alpha1D Ca channel expressed in tsA201 cells using cell-attached configuration. Unitary currents were recorded in the presence of 70 mM Ba2+ as the charge carrier at room temperature. Under basal condition, channel activity was rare and infrequent; however, Bay K 8644 (1 microM) induced channel openings with a conductance of 22.3 pS. Single channel analysis of open and closed time distributions were best fitted with a single exponential. PKC activation by 4alpha-phorbol 12-myristate 13-acetate (PMA; 10 nM), a phorbol ester derivative, resulted in a decrease in open probability and increase in closed-time without any significant effect on the conductance of the alpha1D Ca channel. This is consistent with a decreased entry of alpha1D Ca channel into open states in the presence of PMA. PMA effects could not be reproduced by 4-alpha Phorbol, an inactive PMA analogue. These data show, for the first time, (1) the alpha1D Ca channel activity at the single-channel level and (2) the biophysical basis by which PKC activation inhibits the alpha1D Ca channel. The shortening of the open-time and the lengthening of the closed-time constants and the increase in blank sweeps may explain the inhibition of the previously reported whole-cell alpha1D Ca current. Altogether, these data are essential for understanding the complex role of alpha1D Ca channel not only in physiological settings but also in pathological settings such as atrial fibrillation.
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Zhang X, Kong J, Qu Y. Isolation and characterization of a Lactobacillus fermentum temperate bacteriophage from Chinese yogurt. J Appl Microbiol 2007; 101:857-63. [PMID: 16968297 DOI: 10.1111/j.1365-2672.2006.03007.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AIMS The aim of this study was to investigate the properties of temperate bacteriophage of Lactobacillus fermentum, based on its morphology, restriction patterns, protein profile and the impact on the growth of host strain. METHODS AND RESULTS With Mitomycin C, seven temperate phages were induced from Lactobacilli derived from Chinese yogurt. The temperate phages induced belong to the most common Bradley's group B, having hexagonal head and long, noncontractile tail. They were furthermore confirmed to be the same bacteriophage by identical restriction patterns. SDS-PAGE profile showed that the phage studied had one major structure protein about 31.9 kDa. The presence of the prophage influenced the cell shape and colony size of its lysogenic strain. CONCLUSIONS The phage obtained had similar, but not complete identical properties with other L. fermentum phages reported. It influenced the growth behaviour of its lysogenic strain. SIGNIFICANCE AND IMPACT OF THE STUDY This study provides some information about bacteriophages occurring in the Chinese yoghurt manufacture and contributes to our knowledge on the bacteriophage diversity in the dairy industry.
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Mayer KL, Qu Y, Bansal S, LeBlond PD, Jenney FE, Brereton PS, Adams MWW, Xu Y, Prestegard JH. Structure determination of a new protein from backbone-centered NMR data and NMR-assisted structure prediction. Proteins 2006; 65:480-9. [PMID: 16927360 DOI: 10.1002/prot.21119] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Targeting of proteins for structure determination in structural genomic programs often includes the use of threading and fold recognition methods to exclude proteins belonging to well-populated fold families, but such methods can still fail to recognize preexisting folds. The authors illustrate here a method in which limited amounts of structural data are used to improve an initial homology search and the data are subsequently used to produce a structure by data-constrained refinement of an identified structural template. The data used are primarily NMR-based residual dipolar couplings, but they also include additional chemical shift and backbone-nuclear Overhauser effect data. Using this methodology, a backbone structure was efficiently produced for a 10 kDa protein (PF1455) from Pyrococcus furiosus. Its relationship to existing structures and its probable function are discussed.
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Yuan C, Kaneniwa M, Wang X, Chen S, Cheng Y, Qu Y, FUKUDA Y, Konno K. Seasonal Expression of 2 Types of Myosin with Different Thermostability in Silver Carp Muscle (Hypophthalmichthys molitrix). J Food Sci 2006. [DOI: 10.1111/j.1365-2621.2006.tb12386.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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160
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Bradford R, Abdul Manan R, Daley AJ, Pearce C, Ramalingam A, D'Mello D, Mueller Y, Uahwatanasakul W, Qu Y, Grando D, Garland S, Deighton M. Coagulase-negative staphylococci in very-low-birth-weight infants: inability of genetic markers to distinguish invasive strains from blood culture contaminants. Eur J Clin Microbiol Infect Dis 2006; 25:283-90. [PMID: 16598472 DOI: 10.1007/s10096-006-0130-2] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Selected coagulase-negative staphylococci from the blood of very-low-birth-weight infants in the Neonatal Intensive Care Unit at the Royal Women's Hospital, Melbourne, collected over a 5-year period were examined. Isolates were classified as invasive or contaminants, speciated, typed by pulsed-field gel electrophoresis, and examined for biofilm genes (icaA, icaC, and icaD), adhesion genes (atlE, fbe), and the number of copies of IS256. Of the 24 isolates studied, there were 13 contaminants and 11 invasive isolates. The collection included 15 Staphylococcus epidermidis, eight Staphylococcus capitis, and one each of Staphylococcus warneri and Staphylococcus haemolyticus. Two small clusters of S. epidermidis that belonged to the same molecular type were identified. All S. capitis isolates belonged to the same molecular type or subtype, suggesting that a particular clone was circulating in the unit. There was no significant difference in the species found, the presence of icaA, icaC, icaD, atlE, or fbe, or the number of copies of IS256 between invasive isolates and contaminants. A series of nasal isolates from nonhospitalized adults differed from hospital isolates in the absence of IS256 and the low prevalence of icaC. There was no evidence of IS256-mediated insertion into ica genes as a mechanism of phase variation. These findings suggest that contaminants and invasive isolates derived from the same pool of hospital strains capable of causing sepsis in compromised hosts and that other mechanisms of phase variation exist, apart from IS256 insertion into ica genes.
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Yang BC, Yu QF, Li ZS, Qu Y, Huang Y, Chen JY, Gu ZW, Zhang XD. Preparation of bioactive nanotitania ceramics with biomechanical compatibility. J Biomed Mater Res A 2006; 79:210-5. [PMID: 16871515 DOI: 10.1002/jbm.a.30869] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In this article, bioactive nanotitania ceramics with biomechanical compatibility was prepared by using an additive of hydroxyapatite or MgO as particle growth inhibitor. After sintering at 1000 degrees C, the particle size of nanotitania ceramics prepared by using HA as additive (HT) was much smaller than that prepared by using MgO as additive (MT). In simulated body fluid (SBF), HT could induce apatite formation in 4 days, while no apatite could be found on MT even after it was soaked in SBF for 14 days. After Ros17/28 osteoblasts were cultured on the materials for 1, 4, and 6 days, MTT results showed that the osteoblasts on the HT differentiated faster than that on the MT. Mechanical tests results showed that the bending and compressive strength of HT were 160 and 200 MPa, while those of MT were 70 and 88 MPa, respectively. These results demonstrated that it is suitable to prepare bioactive nanotitania ceramics, with biomechanical compatibility, by using HA as particle growth inhibitor.
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Kazda C, Trautmann M, Brodows RG, Glass LC, Johns D, Qu Y, Bugler CF, Kim D, Holcombe JH. Unterschiedlicher Einfluss von Exenatide und Insulin Glargin auf die postprandialen Blutzuckerspitzen bei Typ 2 Diabetes. DIABETOL STOFFWECHS 2006. [DOI: 10.1055/s-2006-943779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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163
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Dilmanian F, Qu Y, Liu S, Cool C, Gilbert J, Hainfeld J, Kruse C, Laterra J, Lenihan D, Nawrocky M, Pappas G, Sze CI, Yuasa T, Zhong N, Zhong Z, McDonald J. X-ray microbeams: Tumor therapy and central nervous system research. NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH. SECTION A, ACCELERATORS, SPECTROMETERS, DETECTORS AND ASSOCIATED EQUIPMENT 2005; 548:30-37. [PMID: 17369874 PMCID: PMC1828126 DOI: 10.1016/j.nima.2005.03.062] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Irradiation with parallel arrays of thin, planar slices of X-ray beams (microplanar beams, or microbeams) spares normal tissue, including the central nervous system (CNS), and preferentially damages tumors. The effects are mediated, at least in part, by the tissue's microvasculature that seems to effectively repair itself in normal tissue but fails to do so in tumors. Consequently, the therapeutic index of single-fraction unidirectional microbeam irradiations has been shown to be larger than that of single-fraction unidirectional unsegmented beams in treating the intracranial rat 9L gliosarcoma tumor model (9LGS) and the subcutaneous murine mammary carcinoma EMT-6. This paper presents results demonstrating that individual microbeams, or arrays of parallel ones, can also be used for targeted, selective cell ablation in the CNS, and also to induce demyelination. The results highlight the value of the method as a powerful tool for studying the CNS through selective cell ablation, besides its potential as a treatment modality in clinical oncology.
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Qu Y, Guo JT, Olman V, Xu Y. Protein fold recognition through application of residual dipolar coupling data. PACIFIC SYMPOSIUM ON BIOCOMPUTING. PACIFIC SYMPOSIUM ON BIOCOMPUTING 2004:459-70. [PMID: 14992525 DOI: 10.1142/9789812704856_0043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
Residual dipolar coupling (RDC) represents one of the most exciting emerging NMR techniques for studying protein structures. However, solving a protein structure using RDC data alone is a highly challenging problem as it often requires that the starting structure model be close to the actual structure of a protein, for the structure calculation procedure to be effective. We report in this paper a computer program, RDC-PROSPECT, for identification of a structural homolog or analog of a target protein in PDB, which best matches the 15N-1H RDC data of the protein recorded in a single ordering medium. The identified structural homolog/analog can then be used as a starting model for RDC-based structure calculation. Since RDC-PROSPECT uses only RDC data and predicted secondary structure information, its performance is virtually independent of sequence similarity between a target protein and its structural homolog/analog, making it applicable to protein targets out of the scope of current protein threading techniques. We have tested RDC-PROSPECT on all 15N-1H RDC data (representing 33 proteins) available in the BMRB database and the literature. The program correctly identified the structural folds for approximately 80% of the target proteins, significantly better than previously reported results, and achieved an average alignment accuracy of 97.9% residues within 4-residue shift. Through a careful algorithmic design, RDC-PROSPECT is at least one order of magnitude faster than previously reported algorithms for principal alignment frame search, making our algorithm fast enough for large-scale applications.
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Zhu HL, Qu Y, You ZL, Tan MY, Liu WS, Ma JL. Crystal structure of trans-diaqua-bis(salicylaldehydato-O,O′)chromium(III)chloride,[Cr(C7H5O2)2(H2O)2]Cl. Z KRIST-NEW CRYST ST 2003. [DOI: 10.1524/ncrs.2003.218.jg.551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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166
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Zhu HL, Qu Y, You ZL, Tan MY, Liu WS, Ma JL. Crystal structure of trans-diaqua-bis(salicylaldehydato-O,O′) chromium(III) chloride, [Cr(C7H5O2)2(H2O)2]Cl. Z KRIST-NEW CRYST ST 2003. [DOI: 10.1524/ncrs.2003.218.4.519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract C14H14ClCrO6, monoclinic, P121/c1 (No. 14), a = 8.998(18) Å, b = 18.68(4) Å, c = 4.945(10) Å, β = 105.95(2)°, V = 799.2 Å3, Z = 2, Rgt(F) = 0.069, wRref(F2) = 0.170, T = 298 K.
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Qu Y, Vadivelu S, Choi L, Liu S, Lu A, Lewis B, Girgis R, Lee CS, Snider BJ, Gottlieb DI, McDonald JW. Neurons derived from embryonic stem (ES) cells resemble normal neurons in their vulnerability to excitotoxic death. Exp Neurol 2003; 184:326-36. [PMID: 14637103 DOI: 10.1016/j.expneurol.2003.07.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We determined whether embryonic stem (ES) cells could provide a model system for examining neuronal death mediated by glutamate receptors. Although limited evidence indicates that normal neurons can be derived from mouse ES cells, there have been no studies examining pathophysiological responses in mouse ES cell systems. Mouse ES cells, induced down a neural lineage by retinoic acid (RA), were found to have enhanced long-term survival when plated onto a layer of cultured mouse cortical glial cells. In these conditions, the ES cells differentiated into neural cells that appeared normal morphologically and displayed normal features of immunoreactivity when tested for neuron-specific elements. Varying the culture medium generated cultures of mixed neuronal/glial cells or enriched in oligodendrocytes. These cultures were viable for at least four weeks. Real-time PCR analysis of N-methyl-D-aspartate (NMDA) receptor subunits revealed an appropriate age-in-vitro dependent pattern of expression. Neurons derived from ES cells were vulnerable to death induced by a 24-h exposure to the selective glutamate receptor agonists NMDA, kainate, and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA). This vulnerability to agonist-induced death increased with age in vitro, and related closely to expression of receptor subunits, as it does in cultured primary neurons. Experiments with selective receptor antagonists showed that glutamate receptors mediated the NMDA- and kainate-induced death. Neuronal differentiated ES cells therefore exhibited an excitotoxic response resembling that displayed by central nervous system (CNS) neurons. Thus, ES cells, which are very amenable to genetic manipulation, provide a valid system for studying glutamate receptor-mediated toxicity at the molecular level.
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Eysel UT, Schweigart G, Mittmann T, Eyding D, Qu Y, Vandesande F, Orban G, Arckens L. Reorganization in the visual cortex after retinal and cortical damage. Restor Neurol Neurosci 2003; 15:153-64. [PMID: 12671230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
Retinal and cortical lesions are completely different events that trigger visual cortical plasticity. We therefore compared the cortical effects of homonymous lesions of the central retina with effects of cortical lesions. All in vivo experiments were performed in anaesthetized, adult cats. Retinal lesions were made with a Xenon-light photocoagulator, and cortical lesions were induced by focal application of heat or ibotenic acid injection. Both, in cortical regions representing the retinal scotoma and at the border of small focal cortical lesions single neuron activity was initially suppressed and accompanied by a narrow area of increased activity adjacent to the region of functional loss during the first 1-2 weeks. At the same time an increased glutamatergic NMDA response and a reduction of GABA(A) and GABA(B) responses was observed around the cortical lesions in vitro. At an early stage long-term potentiation (LTP) is facilitated in those regions that were characterized by local upregulation of excitation and downregulation of inhibition after cortical lesions. Similarly, at the border of cortical scotomas in area 17 an increased glutamate level was found while inside the scotoma GAD levels were reduced. Shifts in topography of retinal representation as well as increases of receptive field size were detected as signs of lesion-induced neuronal reorganization after retinal and cortical lesions with longer survival times. A common cascade of events is triggered in the visual cortex by retinal as well as cortical lesions: reduced GABAergic inhibition and increased glutamatergic excitation, leading to increased spontaneous activity and visual excitability that is accompanied by facilitated LTP, and appears to initiate local cortical reorganization after functional disturbances in the visual system.
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Qu Y, Liu SQ, Peng WZ, Liu BL. [Inhibition of telomerase activity by ribozyme targeted to human telomerase transcriptase]. SHENG WU HUA XUE YU SHENG WU WU LI XUE BAO ACTA BIOCHIMICA ET BIOPHYSICA SINICA 2002; 34:323-8. [PMID: 12019445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
Human telomerase reverse transcriptase (hTERT) is the catalytic subunit and the key factor which controls the telomerase activity,so it is the best choice to inhibit telomerase through controling hTERT expression.In this work,a hammer head ribozyme directed against the hTERT mRNA (hTERTRZ) was designed and synthesized to serve as a telomerase inhibitor. In order to test its in vitro cleavage activity, two in vitro transcription plasmids containing hTERTRZ and hTERT gene respectively were constructed. Ribozyme RNA and DIG-labeled-hTERT were synthesized by in vitro transcription. In vitro cleavage reactions were carried out by mixing the hTERTRZ with DIG-labeled-hTERT under different reaction conditions, and cleavage bands were detected by digoxin chemiluminescent assay. hTERTRZ showed a specific cleavage activity against the hTERT used as template. To investigate its in vivo effect of telomerase inhibition in tumor cells, a eukaryotic expression plasmid containing the hTERT ribozyme gene was introduced into HeLa cells and hepatoma cells by using LipofectAMINE. In the transfectants, the level of intact hTERT mRNA and the telomerase activity were clearly reduced, and the telomere length of these clones was apparently shortened at the beginning period, then kept a fixed value without further shortening. All the transfectants with ribozyme grew clearly more slowly than the parental cell line. The doubling time of the tansfectants prolonged compared to the negative control, but no apparent apoptosis was shown even at their 37th passage. These findings suggest the potential application of this ribozyme as a new theraputic agent directed against immortalized cancer cells.
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Hadgu A, Qu Y. A biomedical application of latent class models with random effects. J R Stat Soc Ser C Appl Stat 2002. [DOI: 10.1111/1467-9876.00131] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Qu Y, Fitzgerald JA, Rauter H, Farrell N. Approaches to selective DNA binding in polyfunctional dinuclear platinum chemistry. The synthesis of a trifunctional compound and its interaction with the mononucleotide 5'-guanosine monophosphate. Inorg Chem 2001; 40:6324-7. [PMID: 11703138 DOI: 10.1021/ic010584l] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Hegmans A, Qu Y, Kelland LR, Roberts JD, Farrell N. Novel approaches to polynuclear platinum pro-drugs. Selective release of cytotoxic platinum-spermidine species through hydrolytic cleavage of carbamates. Inorg Chem 2001; 40:6108-14. [PMID: 11703107 DOI: 10.1021/ic010509a] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BBR3464 is a novel trinuclear platinum drug currently in Phase II clinical trials. Polyamine-bridged dinuclear platinum compounds as represented by [[trans-Pt(NH(3))(2)Cl](2)-mu-spermidine-N(1),N(8)]Cl(3) (1) are highly interesting second-generation analogues of BBR3464 because the hydrogen-bonding and electrostatic contributions of the central platinum-amine group in BBR3464 are replicated by the free, noncoordinated "central" quaternary nitrogens of the linear polyamine linker while the presence of two separate Pt-Cl bonds maintains the bifunctional binding mode on the DNA adducts. Preclinical investigations confirm the potency of these species with cytotoxicity in the nanomolar range. This remarkable potency results in a relatively narrow therapeutic index. To enhance the therapeutic index of these drugs, we investigated the potential for "pro-drug" delivery of less toxic and better tolerated derivatives such as the compounds [[trans-Pt(NH(3))(2)Cl](2)-mu-N(4)-R-spermidine-N(1),N(8)]Cl(2) where N(4)-R represents BOC (tert-butyl), CBz (benzyl), and Fmoc (fluorenylmethyl) carbamate blocking groups, 2-4, respectively. The bulky Fmoc derivative showed evidence for conformational isomers by (1)H NMR spectroscopy due to the inequivalence of the two n-propyl and n-butyl side chains of the spermidine moiety. The rate constants for hydrolysis and release of 1 were calculated. Release of cytotoxic 1 at physiologically relevant pH followed the order 4 > 2 > 3. The calculated values for 4 (pH 5, 6.0(+/-3.9) x 10(-10) s(-1); pH 6, 6.5(+/-0.2) x 10(-9) s(-1); pH 7, 6.0(+/-0.2) x 10(-8) s(-1); pH 8, 1.6(+/-0.1) x 10(-7) s(-1)) show a more pronounced pH dependence compared to 2 (pH 5, 4.6(+/-0.1) x 10(-8) s(-1); pH 6, 4.2(+/-0.1) x 10(-8) s(-1); pH 7, 3.2(+/-0.1) x 10(-8) s(-1)). Preliminary biological assays of cellular uptake and cytotoxicity confirm the utility of the pro-drug concept. While blocked-polyamine compounds such as 2-4 are, in general, 2-3 orders of magnitude less cytotoxic than 1, there is significant cell type variability. Specifically, the Fmoc derivative 4 showed significantly enhanced cytotoxicity warranting further study of the pro-drug concept for greater selectivity and/or oral delivery.
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173
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Abstract
In this study we report, for the first time, on the gene expression of human cardiac SERCA2a, L-type (alpha(1C)) and T-type (alpha(1H)) Ca channels during development, using RNase protection assay, relative quantitative RT-PCR and Western blot. Human hearts during early gestation (8- to 20-wk gestation), neonatal (1- to 4-d-old) and adult (18- to 48-year-old) stages were used. The results show that T-type Ca channel alpha(1H) subunit mRNA decreased and that L-type Ca channel alpha(1C) subunit mRNA increased with development. While the levels of sarcoplasmic reticulum ATPase (SERCA2a) mRNA did not significantly change with development, its protein levels increased with development. In conclusion, SERCA2a, L-type and T-type Ca channel transcripts were detected as early as 8-wk gestation. Defining the profile of Ca handling proteins during development is important to the understanding of excitation-contraction (EC)-coupling of the developing human heart.
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MESH Headings
- Adult
- Base Sequence
- Blotting, Western
- Calcium Channels, L-Type/genetics
- Calcium Channels, T-Type/genetics
- Calcium-Transporting ATPases/genetics
- DNA Primers
- Heart/embryology
- Humans
- Infant, Newborn
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Ribosomal, 18S/genetics
- RNA, Ribosomal, 18S/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Sarcoplasmic Reticulum Calcium-Transporting ATPases
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174
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Xiao GQ, Qu Y, Sun ZQ, Mochly-Rosen D, Boutjdir M. Evidence for functional role of epsilonPKC isozyme in the regulation of cardiac Na(+) channels. Am J Physiol Cell Physiol 2001; 281:C1477-86. [PMID: 11600410 DOI: 10.1152/ajpcell.2001.281.5.c1477] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Investigation of the role of individual protein kinase C (PKC) isozymes in the regulation of Na(+) channels has been largely limited by the lack of isozyme-selective modulators. Here we used a novel peptide-specific activator (epsilonV1-7) of epsilonPKC and other peptide isozyme-specific inhibitors in addition to the general PKC activator phorbol 12-myristate 13-acetate (PMA) to dissect the role of individual PKCs in the regulation of the human cardiac Na(+) channel hH1, heterologously expressed in Xenopus oocytes. Peptides were injected individually or in combination into the oocyte. Whole cell Na(+) current (I(Na)) was recorded using two-electrode voltage clamp. epsilonV1-7 (100 nM) and PMA (100 nM) inhibited I(Na) by 31 +/- 5% and 44 +/- 8% (at -20 mV), respectively. These effects were not seen with the scrambled peptide for epsilonV1-7 (100 nM) or the PMA analog 4alpha-phorbol 12,13-didecanoate (100 nM). However, epsilonV1-7- and PMA-induced I(Na) inhibition was abolished by epsilonV1-2, a peptide-specific antagonist of epsilonPKC. Furthermore, PMA-induced I(Na) inhibition was not altered by 100 nM peptide-specific inhibitors for alpha-, beta-, delta-, or etaPKC. PMA and epsilonV1-7 induced translocation of epsilonPKC from soluble to particulate fraction in Xenopus oocytes. This translocation was antagonized by epsilonV1-2. In native rat ventricular myocytes, PMA and epsilonV1-7 also inhibited I(Na); this inhibition was antagonized by epsilonV1-2. In conclusion, the results provide evidence for selective regulation of cardiac Na(+) channels by epsilonPKC isozyme.
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175
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Qu Y, Curtis R, Lawson D, Gilbride K, Ge P, DiStefano PS, Silos-Santiago I, Catterall WA, Scheuer T. Differential modulation of sodium channel gating and persistent sodium currents by the beta1, beta2, and beta3 subunits. Mol Cell Neurosci 2001; 18:570-80. [PMID: 11922146 DOI: 10.1006/mcne.2001.1039] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Brain sodium channels are complexes of a pore-forming alpha subunit with auxiliary beta subunits, which are transmembrane proteins that modulate alpha subunit function. The newly cloned beta3 subunit is shown to be expressed broadly in neurons in the central and peripheral nervous systems, but not in glia and most nonneuronal cells. Beta1, beta2, and beta3 subunits are coexpressed in many neuronal cell types, but are differentially expressed in ventromedial nucleus of the thalamus, brain stem nuclei, cerebellar Purkinje cells, and dorsal root ganglion cells. Coexpression of beta1, beta2, and beta3 subunits with Na(v)1.2a alpha subunits in the tsA-201 subclone of HEK293 cells shifts sodium channel activation and inactivation to more positive membrane potentials. However, beta3 is unique in causing increased persistent sodium currents. Because persistent sodium currents are thought to amplify summation of synaptic inputs, expression of this subunit would increase the excitability of specific groups of neurons to all of their inputs.
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