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Ballard JE, Prueksaritanont T, Tang C. Hepatic Metabolism of MK-0457, a Potent Aurora Kinase Inhibitor: Interspecies Comparison and Role of Human Cytochrome P450 and Flavin-Containing Monooxygenase. Drug Metab Dispos 2007; 35:1447-51. [PMID: 17537870 DOI: 10.1124/dmd.107.015438] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
MK-0457 (N-[4([4-(4-methylpiperazin-1-yl)-6-[(3-methyl-1H-pyrazol-5 -yl)amino]pyrimidin-2-yl]thio)phenyl]cyclopropanecarboxamide), an Aurora kinase inhibitor in development for the treatment of cancer, was evaluated for its in vitro metabolism in different species. This compound primarily underwent N-oxidation and N-demethylation in human, monkey, dog, and rat liver preparations. However, N-demethylation was less significant in dogs. The formation of minor metabolites varied with species, but all metabolites generated in human hepatocytes were observed in animals. Results of immunoinhibition, selective chemical inhibition, thermal inactivation, and metabolism by recombinant cytochromes P450 and flavin-containing monoogygenases (FMOs) strongly suggest that CYP3A4 and FMO3 comparably contributed to MK-0457 N-oxidation in human liver microsomes, where the reaction conformed to Michaelis-Menten kinetics. These studies indicate a major role of CYP2C8 in the N-demethylation reaction, whereas CYP3A4 only made a minor contribution. However, significant substrate inhibition was observed with MK-0457 N-demethylation at high substrate concentrations (>10 microM) in human liver microsomes relative to the anticipated therapeutic exposure. A multienzyme metabolic pathway such as this may mitigate the potential of drug interactions in clinical treatment with MK-0457.
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Tang C, Qiao YF, Han XZ, Zheng SJ. Genotypic variation in phosphorus utilisation of soybean [Glycine max (L.) Murr.] grown in various sparingly soluble P sources. ACTA ACUST UNITED AC 2007. [DOI: 10.1071/ar06280] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This study compared the utilisation of sparingly soluble P among soybean genotypes selected from 3 geographical regions with contrasting soil pH. Plants of 5 genotypes from each region were grown for 72 days in soil columns supplied with hydroxyapetite (Ca-P), AlPO4 (Al-P), or FePO4 (Fe-P) at a rate of 25 mg P/kg soil. NaH2PO4 (Na-P) was used as control at the same rate. Shoot weights ranged from 2.4 to 5.9 g/plant. On average, the genotypes selected from calcareous soils of north-west China produced the highest shoot biomass whereas those from neutral soils of the north-east region the least. Root biomass and root surface area followed the same trend. In contrast, the root-to-shoot weight ratio was highest in Fe-P and lowest in Na-P while root length in Na-P and Fe-P was greater than in the other P forms. The genotypes from the north-east region had higher P concentration in the shoot than those from the other 2 regions. Total P uptake ranged from 9.0 to 15.9 mg/plant for Na-P, and from 6.3 to 12.4 for the sparingly soluble P. Average total P uptake was the highest for the genotypes from the north-west region, and was greatest in Na-P and lowest in Fe-P. The genotypes from the north-east region displayed the greatest ability to use sparingly soluble P, and those from the north-west the least relative to Na-P. Total P uptake from the sparingly soluble P correlated highly with plant biomass production, N2 fixation and nodulation, and seed P, while the relative P uptake correlated highly with P concentration in shoots but neither correlated with root carboxylate release nor leachate pH. The results suggest that there is a substantial genotypic variation in utilisation of sparingly soluble P, which is related to early vigour, nodulation, and seed P reserve but not to origin site pH or root exudation.
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Chapman H, Tang C, Robillard L, Kim Y, Wei Y. ID: 294 Tumor Cell Signaling Through Integrin alpha5beta1 Requires Urokinase Receptor Binding. J Thromb Haemost 2006. [DOI: 10.1111/j.1538-7836.2006.00294.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Liu CH, Mishra AK, Tan RX, Tang C, Yang H, Shen YF. Repellent and insecticidal activities of essential oils from Artemisia princeps and Cinnamomum camphora and their effect on seed germination of wheat and broad bean. BIORESOURCE TECHNOLOGY 2006; 97:1969-73. [PMID: 16230008 DOI: 10.1016/j.biortech.2005.09.002] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2005] [Revised: 09/01/2005] [Accepted: 09/03/2005] [Indexed: 05/04/2023]
Abstract
Repellent and insecticidal activities of essential oils extracted from leaves of Artemisia princeps Pamp and seeds of Cinnamomum camphora (L.) Presl. against storage pests Sitophillus oryzae L. and Bruchus rugimanus Bohem were investigated. Results showed that the two individual oils displayed good, but their mixture (1:1) exhibited much better repellent activities at concentrations from 250 to 1000 microg g(-1) and insecticidal actions at concentrations 1000 microg g(-1) against the test beetles S. oryzae and B. rugimanus. Oils from A. princeps and C. camphora applied individually were significantly toxic to seed germination of wheat at 500 microg ml(-1). However, no toxic effects were found when the two oils were mixed (1:1 w/w) at the same concentration. These observations indicated that the mixture of the two plant-derived oils had a synergic effect and could be used in the control of storage pests.
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Zhang S, Yang JH, Yu F, Zhao J, Jiang P, Chang L, Tang C, Xu J. Protective role of 3-nitro-N-methyl-salicylamide on isolated rat heart during 4 hours of cold storage and reperfusion. Transplant Proc 2006; 38:1247-52. [PMID: 16797274 DOI: 10.1016/j.transproceed.2006.02.061] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2005] [Indexed: 10/24/2022]
Abstract
OBJECTIVE Cardiac ischemia/reperfusion (I/R) injury, a necessary consequence of transplantation, is probably related to the formation of reactive oxygen species (ROS). The ROS burst within the first moments of reperfusion is associated with injury, continuously generate O2- at about 3% to 5% of total O2 consumption owing to electron leak by mitochondrial oxidoreductases, especially complexes I and III. 3-nitro-N-methyl-salicylamide (NNMS) displays inhibitory effects on succinate-cytochrome C reductase, but also reduces effects on creation of O2- radical and H2O2 by isolated rat mitochondria. Presumably NNMS inhibits electron leakage from the mitochondrial respiratory chain. We investigated effect of NNMS on heart protection after hypothermic ischemia. METHODS A Langendorff-prepared rat heart model was employed after the heart had been preserved for 4 hours under hypothermic conditions of ischemia with subsequent reperfusion/rewarming for 60 minutes. RESULTS The group of hearts treated with NNMS showed increased recovery of heart function compared with a group of mEC. The lactate dehydrogenase (LDH) activity in coronary flow (CF) by hearts treated with NNMS was lower than that with mECs, as was the content of malonedialdehyde (MDA) and conjugated diene (CD). CONCLUSIONS NNMS improved heart physiology after reperfusion following 4 hours of hypothermic ischemia.
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Bhandari V, Choo-Wing R, Chapoval SP, Lee CG, Tang C, Kim YK, Ma B, Baluk P, Lin MI, McDonald DM, Homer RJ, Sessa WC, Elias JA. Essential role of nitric oxide in VEGF-induced, asthma-like angiogenic, inflammatory, mucus, and physiologic responses in the lung. Proc Natl Acad Sci U S A 2006; 103:11021-6. [PMID: 16832062 PMCID: PMC1544167 DOI: 10.1073/pnas.0601057103] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2006] [Indexed: 12/30/2022] Open
Abstract
VEGF, nitric oxide (NO), inflammation, and vascular- and extravascular remodeling coexist in asthma and other disorders. In these responses, VEGF regulates angiogenesis. VEGF also induces inflammation and remodeling. The mechanisms of the latter responses have not been defined, however. We hypothesized that VEGF-induces extravascular tissue responses via NO-dependent mechanisms. To evaluate this hypothesis, we compared the effects of transgenic VEGF165 in lungs from normal mice, mice treated with pan-NO synthase (NOS) or endothelial NOS (eNOS) inhibitors, and mice with null mutations of inducible NOS (iNOS) or eNOS. These studies demonstrate that VEGF selectively stimulates eNOS and iNOS. They also demonstrate that VEGF induces pulmonary alterations via NO-dependent and -independent mechanisms with angiogenesis, edema, mucus metaplasia, airway hyperresponsiveness, lymphocyte accumulation, dendritic cell hyperplasia and S-nitrosoglutathione reductase stimulation being NO-dependent and dendritic cell activation being NO-independent. Furthermore, they demonstrate that eNOS and iNOS both contribute to these responses. NO/NOS-based interventions may be therapeutic in VEGF-driven inflammation and remodeling.
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Huang SJ, Schatz F, Masch R, Rahman M, Buchwalder L, Niven-Fairchild T, Tang C, Abrahams VM, Krikun G, Lockwood CJ. Regulation of chemokine production in response to pro-inflammatory cytokines in first trimester decidual cells. J Reprod Immunol 2006; 72:60-73. [PMID: 16806486 DOI: 10.1016/j.jri.2006.03.002] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2005] [Revised: 02/28/2006] [Accepted: 03/08/2006] [Indexed: 01/28/2023]
Abstract
OBJECTIVE Chemokines initiate the immune response by controlling leukocyte migration and lymphocyte development. Macrophage infiltration of the decidua has been implicated in the genesis of recurrent miscarriage and preeclampsia. Therefore, we determined whether cultured human decidual cells produce monocyte/macrophage-recruiting chemokines in response to a potent pro-inflammatory cytokine, interleukin-1beta (IL-1beta), and whether decidual cell-conditioned medium contains monocyte- and macrophage-chemoattractant activity. METHODS Leukocyte-free first trimester decidual cells were treated for 6h with estradiol (E(2)) and medroxyprogesterone acetate (MPA) to mimic the steroidal milieu of pregnancy, or E(2) and MPA and IL-1beta (1 ng/ml) to mimic inflamed decidua. Total RNA was used for cDNA synthesis. Biotinylated cRNAs were generated and chemically fragmented for hybridization on Affymetrix HG_U133 Plus 2.0 chips followed by fluorescence labeling and optical scanning. Raw data generated from Affymetrix GCOS 1.2 (GeneChip Operating Software) were analyzed by GeneSpring 7.2 software. Subsequently microarray results were validated by real time RT-PCR and Western blotting. A functional study of monocyte migration was carried out also using conditioned media from culture. RESULTS Five chemokines responsible for monocyte/macrophage chemoattraction and activation, including C-C motif ligand 2 (CCL2), CCL5, C-X-C motif ligand 2 (CXCL2), CXCL3 and CXCL8, were markedly elevated from 29- to 975-fold after exposure to IL-1beta in cultured first trimester decidual cells. The results of real-time RT-PCR (up-regulation from 43- to 3069-fold) and Western blotting (up-regulation from 15- to 300-fold) confirmed the microarray findings. Monocyte migration was significantly induced by the conditioned medium from IL-1beta-treated decidual cells. CONCLUSIONS Treatment of first trimester decidual cells with IL-1beta induces secretion of monocyte/macrophage recruiting-chemokines and promotes monocyte migration. Extrapolation of these in vitro results to the milieu of implantation site suggests a mechanism whereby IL-1beta could mediate excessive macrophage infiltration of the decidua.
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Saha S, Muthu D, Golberg D, Tang C, Zhi C, Bando Y, Sood A. Comparative high pressure Raman study of boron nitride nanotubes and hexagonal boron nitride. Chem Phys Lett 2006. [DOI: 10.1016/j.cplett.2006.01.062] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Tang C, Wu A, Leong E, Fears T, Azzi R, O'Shannessy D, Lin A. Detection, Analysis and Significance of Guanylyl Cyclase C in the Lymph Nodes from Patients with Colorectal Cancer. J Investig Med 2006. [DOI: 10.1177/108155890605401s155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Tang C, Wu A, Leong E, Fears T, Azzi R, O'Shannessy D, Lin A. 272 DETECTION, ANALYSIS AND SIGNIFICANCE OF GUANYLYL CYCLASE C IN THE LYMPH NODES FROM PATIENTS WITH COLORECTAL CANCER. J Investig Med 2006. [DOI: 10.2310/6650.2005.x0004.271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Sargeant M, Sale P, Tang C. Salt priming improves establishment of Distichlis spicata under saline conditions. ACTA ACUST UNITED AC 2006. [DOI: 10.1071/ar06103] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Salt priming as a tool to establish Distichlis spicata (L.) Greene cv. Yensen-4a (NyPa Forage) plants into saline conditions was investigated in sand culture. Plants were pre-treated with 3 levels of salinity (0, 2, and 4 g NaCl/kg sand) for 36 days and then transplanted into 4 salinity treatments of 0, 2, 4, and 8 g NaCl/kg sand. Soil electrical conductivity (EC), Na and Cl concentrations in the sand, growth initiation, tiller formation, dry matter production, and salt excretion and uptake were measured. Plants pre-treated with 4 g NaCl/kg sand produced 6-fold more dry matter than plants pre-treated with 0 and 2 g NaCl/kg sand when transplanted into sand containing 2 g NaCl/kg. Survival and tiller formation were also higher with plants that had been pre-treated with 4 g NaCl/kg sand compared with plants pre-treated with 0 and 2 g NaCl/kg, when transplanted into 2 and 4 g NaCl/kg sand. The results suggest that salt priming improves establishment of Distichlis spicata when transplanted into low to moderate salinity conditions.
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Lam MF, Lo WK, Tang C, Lui SL, Chan TM, Lai KN. Transport of Small Solutes in Peritonitis-free PD Patients. Int J Organ Transplant Med 2005. [DOI: 10.1016/s1561-5413(09)60198-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Lin J, Huang Y, Ding XX, Cheng C, Tang C, Qi SR. Metal oxide coating on carbon nanotubes by a methanol-thermal method. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2005; 5:932-6. [PMID: 16060156 DOI: 10.1166/jnn.2005.120] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
A methanol-thermal method has been developed to fabricate one-dimensional composite nanowires by coating multiwalled carbon nanotubes with lanthanum oxide and iron oxide, respectively. The coating structure and composition have been investigated by transmission electron microscopy and the X-ray energy dispersive spectrum. Magnetic measurement for the iron oxide coatings indicated that the coercivity has been enhanced after coating. The method reported here provides a novel procedure for the fabrication of one-dimensional composite nanostructures.
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Lin AY, Fisher G, So S, Tang C, Levitt L. A phase II study of imatinib mesylate (IM) in patients (pts) with unresectable hepatocellular carcinoma (HCC). J Clin Oncol 2005. [DOI: 10.1200/jco.2005.23.16_suppl.4223] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Hu L, Li YX, Qu JP, Huang ZX, Huang XT, Ding XX, Tang C, Qi SR. MgO nanowire growth from Mg metal and SiO2. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2004; 4:1071-1075. [PMID: 15656205 DOI: 10.1166/jnn.2004.136] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Comparative study on the diameter distribution of MgO nanowires has been carried out. MgO nanowires could be synthesized by the direct reaction between metallic magnesium and silica, and the obtained nanowires have diameters ranging from 50 to 200 nm and lengths of several hundreds nanometers, exhibiting a straight wire. The diameter can be downscaled to smaller than 50 nm, and the nanowire exhibits a curved and twisted one-dimensional structure with lengths up to several micrometers, when a fine support catalyst was used as the reactant. The diameter-controlled growth mechanism was also explained in this work.
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Kloster M, Tang C, Wingreen NS. Finding regulatory modules through large-scale gene-expression data analysis. ACTA ACUST UNITED AC 2004; 21:1172-9. [PMID: 15513996 DOI: 10.1093/bioinformatics/bti096] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
MOTIVATION The use of gene microchips has enabled a rapid accumulation of gene-expression data. One of the major challenges of analyzing this data is the diversity, in both size and signal strength, of the various modules in the gene regulatory networks of organisms. RESULTS Based on the iterative signature algorithm [Bergmann,S., Ihmels,J. and Barkai,N. (2002) Phys. Rev. E 67, 031902], we present an algorithm-the progressive iterative signature algorithm (PISA)-that, by sequentially eliminating modules, allows unsupervised identification of both large and small regulatory modules. We applied PISA to a large set of yeast gene-expression data, and, using the Gene Ontology database as a reference, found that the algorithm is much better able to identify regulatory modules than methods based on high-throughput transcription-factor binding experiments or on comparative genomics.
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Hu L, Li Y, Ding X, Tang C, Qi S. Insight into carbon nanotubes-template reaction at high temperature. Chem Phys Lett 2004. [DOI: 10.1016/j.cplett.2004.08.131] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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218
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Zhang B, Wang S, Pang Y, Tang C, Du J. Alteration of heme-oxygenase-carbon monoxide pathway in calcified rat vascular smooth muscle cells. ACTA ACUST UNITED AC 2004; 93:109-15. [PMID: 14963676 DOI: 10.1007/s00392-004-0989-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2003] [Accepted: 06/24/2003] [Indexed: 11/27/2022]
Abstract
OBJECTIVE The aim of the present study was to investigate the changes in heme-oxygenase (HO)-carbon monoxide (CO)-cyclic guanosine monophosphate (cGMP) pathway in clacified rat vascular smooth muscle cells (VSMCs). METHODS Calcification of cultured rat VSMCs was induced by incubation of VSMCs with beta-glycerophosphate. Cellular calcium content, ALP activities and (45)Ca uptake were measured. HO activity, HbCO formation and content of cGMP in VSMCs were determined. Immunocytochemistry for HO-1 expression was observed. RESULTS In comparison of control VSMCs, the cellular calcium content, ALP activity and (45)Ca uptake in calcified VSMCs were obviously increased. Immunocytochemistry showed that HO-1 expression was weak and not well distributed in calcified cells as compared to non-calcified VSMCs, but interestingly, there was stronger staining in calcified nodules than in VSMCs. Compared with VSMCs, HO-1 activity in calcified cells decreased by 42.7% [36.4 +/- 2.8 pmol (mg Pr x h)(-1) vs 63.5 x 5.3 pmol (mg Pr x h)(-1), p < 0.01], and HbCO formation decreased by 39.2% (3.38 x 0.69 micromol/mg Pr vs 5.56 +/- 0.48 micromol/mg Pr, p < 0.05). The cGMP content in calcified VSMCs was 78.1% lower than that of non-calcified VSMCs (4.3 +/- 0.51 vs 19.6 +/- 1.2 pmol/mg, p < 0.01). CONCLUSION The results showed that HO-CO-cGMP pathway in calcified vascular cells obviously changed, which might contribute to disturbance of vascular function.
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Chang L, Xu J, Yu F, Zhao J, Tang X, Tang C. Taurine protected myocardial mitochondria injury induced by hyperhomocysteinemia in rats. Amino Acids 2004; 27:37-48. [PMID: 15309570 DOI: 10.1007/s00726-004-0096-2] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2003] [Accepted: 02/18/2004] [Indexed: 11/26/2022]
Abstract
Taurine can protect against cardiovascular diseases, whereas elevated levels of plasma homocysteine are associated with atherosclerotic and thromboembolic cardiovascular diseases. To illustrate the effects of taurine on hyperhomocysteinemia, we observed the myocardial mitochondria dysfunction in the rats with hyperhomocysteinemia induced by diet methionine loading, and the therapeutic effect of taurine. A methionine diet increased plasma homocysteine concentration (133.51 +/- 27.91 micromol/L vs 12.31 +/- 2.58 micromol/L in control, P < 0.01), stimulated the production of reactive oxygen species (ROS) in the myocardial mitochondria, and inhibited the activities of mitochondrial Mn-superoxide dismutase and catalase. The 45Ca uptake and Ca2+-ATPase activity in the myocardial mitochondria were significantly lowered in rats with hyperhomocysteinemia. Taurine supplements effectively attenuated the hyperhomocysteinemia-induced ROS production and inhibition of Mn-superoxide dismutase and catalase activities in the myocardial mitochondria, and increased its 45Ca uptake and Ca2+-ATPase activity. Thus, taurine antagonizes the oxidative stress injury in the myocardial mitochondria induced by the hyperhomocysteinemia.
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Tang C, Chen V. The photocatalytic degradation of reactive black 5 using TiO2/UV in an annular photoreactor. WATER RESEARCH 2004; 38:2775-2781. [PMID: 15207608 DOI: 10.1016/j.watres.2004.03.020] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2003] [Revised: 02/10/2004] [Accepted: 03/12/2004] [Indexed: 05/24/2023]
Abstract
The textile effluent is a major industrial polluter because it is highly colored, containing about 15% unfixed dyes as well as high levels of salts that can potentially be discharged into the environment. Photocatalytic oxidation using an thin gap annular UV reactor with TiO2 was used to break down the colour of a synthetic effluent ranging up to 400 ppm in dye concentration of Reactive Black 5 and up to 80 g/L in NaCl. Results show that the reaction kinetics was dominated by the TiO2 loading, the initial dye concentration, and the dissolved oxygen concentration; with the other parameters showing less significant effects. High rates of decolorization were found, with a linear fit to the Langmuir-Hinshelwood equation yielding a reaction rate constant (k) of 2.45 ppm/min, and an adsorption equilibrium constant (K) of 0.048 ppm(-1) based on color removal. The presence of the combination of high dissolved oxygen (15 ppm) and sodium chloride (up to 80 g/L) was found to enhance the decolorization and mineralization rates of the reactive dye. However, pH was found to not significantly affect the degradation rate. Since textile effluent is strongly alkaline, this result is significant, as no solution neutralisation is required and direct treatment of the effluent is possible.
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Yin W, Liao D, Kusunoki M, Xi S, Tsutsumi K, Wang Z, Lian X, Koike T, Fan J, Yang Y, Tang C. NO-1886 decreases ectopic lipid deposition and protects pancreatic beta cells in diet-induced diabetic swine. J Endocrinol 2004; 180:399-408. [PMID: 15012594 DOI: 10.1677/joe.0.1800399] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The synthetic compound NO-1886 (ibrolipim) is a lipoprotein lipase activator that has been proven to be highly effective in lowering plasma triglycerides. Recently, we found that NO-1886 also reduced plasma free fatty acids and glucose in high-fat/high-sucrose diet-induced diabetic rabbits. In the current study, we investigated the effects of NO-1886 treatment on ectopic lipid deposition and the islet pathology in miniature swine fed a high-fat/high-sucrose diet. Our results showed that feeding this diet to miniature swine caused insulin resistance, increased lipid deposition in non-adipose tissue, such as in the heart, skeletal muscle, liver and pancreas, and also caused pancreatic beta cell damage. However, supplementing 1% NO-1886 (200 mg/kg per day) into the high-fat/high-sucrose diet decreased ectopic lipid deposition, improved insulin resistance, and alleviated the beta cell damage. These results suggest that improvement of lipid disorder, non-adipose tissue steatosis and insulin resistance may be very important for the protection of beta cell damage. Therefore, NO-1886 is potentially beneficial for the treatment of insulin-resistance syndrome.
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Beardsley DJS, Tang C, Chen BG, Lamborn C, Gomes E, Srimatkandada V. The disulfide-rich region of platelet glycoprotein (GP) IIIa contains hydrophilic peptide sequences that bind anti-GPIIIa autoantibodies from patients with immune thrombocytopenic purpura (ITP). Biophys Chem 2003; 105:503-15. [PMID: 14499914 DOI: 10.1016/s0301-4622(03)00111-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Immune thrombocytopenic purpura (ITP) is an autoimmune blood disease caused by autoantibody-mediated destruction of blood platelets. Platelet glycoprotein (GP) IIb/IIIa is a common target for antiplatelet autoantibodies. The present studies were undertaken (1). to confirm whether the disulfide rich repeat region of GPIIIa contains target epitopes for antiplatelet antibodies in patients with ITP; (2). to determine whether these antigens were defined by peptide sequences in the absence of post-translational modification; and (3). to correlate observed immunologic reactivity with the recently solved X-ray crystallographic structure of an analogous integrin complex, the vitronectin receptor, alpha(V)beta(3). Recombinant fusion proteins of four GPIIIa extracellular sequences were prepared and purified. Immunoblotting results with purified recombinant peptides showed potent reactivity of 16 of 24 ITP patient serum anti-GPIIb/IIIa antibodies with the fusion protein containing the GPIIIa sequence of residues from 468 to 691. These results are consistent with a report by Kekomaki et al. that a 50 kDa chymotryptic digestion product of GPIIIa isolated from blood platelets contains target epitopes for serum antiplatelet antibodies in 16 of 33 ITP patients. Smaller peptides including residues 446-501 and residues 593-691 each reacted with only 5 of the 24 patient sera; furthermore all but 3 of these interactions were very weak. Visualization of the conformation of the extracellular portion of alpha(V)beta(3) reveals the location of the 222-residue antigenic GPIIIa (beta(3)) peptide 'B' at the immediately extracellular region of the protein that includes a beta-tail domain and several integrin-EGF domains. In summary, predictions of hydrophilicity, surface accessibility and antigenicity and the three dimensional structure of the beta(3) integrin correlate with autoantibody binding to a recombinant GPIIIa peptide 'B' containing residues 468-691.
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Longino J, Mullen B, Benghuzzi H, Tucci M, Tang C, Storey R, Puckett A. Evaluation of novel biodegradable cyclic carbonate polyester copolymers for cytocompatibility using MRC-5 cells. BIOMEDICAL SCIENCES INSTRUMENTATION 2003; 39:306-11. [PMID: 12724911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
The objective of this work was to synthesize and characterize a novel series of biodegradable cyclic carbonate polyester copolymers based on lactide and 5-methyl-5-benzyloxy-carbonyl-1,3-dioxan-2-one (MBC). Two compositions were selected for characterization. One copolymer was based on a racemic mixture of 1-lactide with 15.4 mole % MBC and the other was based on 1-lactide with 8.2 mole % MBC. These polymers contain carboxylic acid moieties along the backbone that may be used for tethering bioactive agents, forming ionic crosslinks or be reacted with vinyl containing monomers to allow free radical crosslinking. The initial materials evaluated have the carboxylic acid functionalities blocked with benzene. These polymers and the de-blocked versions may have potential applications for hard and soft tissue scaffolds, control drug delivery matrixes or a variety of other applications in medicine. The copolymer samples were pressed into 7.0-mm diameter disk using a KBr press. The disks were then sterilized using U.V radiation under a laminar flow hood. After sterilization, the copolymer disks were submerged in 2 ml of media and placed in a CO2 regulated incubator at 37 degrees C. A total of six groups per phase (n = 7 test tubes per group) were used in this study. Test tubes in groups I and III were plated with MRC-5 and subsequently treated with media alone (controls). Test tubes in groups II and IV were plated with MRC-5 and subsequently treated with media before being introduced to copolymer samples. Cell number, as well as, biochemical markers such as protein and malondialdehyde (MDA) were determined at the end of the 24, 48 and 72-hour time periods. Representative test tubes were subjected to an H&E staining procedure for microscopic morphological evaluation. The results of this evaluation suggest that the exposure of both copolymers produced a non-cytotoxic environment with the MRC-5 cell line. Although both copolymers are non-cytotoxic, the sample having the higher MBC content is the preferred composition based upon MDA levels and morphological evaluations.
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Hughes MA, Tang C, Cherry GW. Effect of intermittent radiant warming on proliferation of human dermal endothelial cells in vitro. J Wound Care 2003; 12:135-7. [PMID: 12715485 DOI: 10.12968/jowc.2003.12.4.26487] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE This study investigated the effect of Warm-Up therapy on the proliferation of human microvascular dermal endothelial cells. METHOD Endothelial cells from an adult subject were seeded in six-well plates and placed in an incubator at 32.5 degrees C. The following day Warm-Up dressings were placed over the plates, with or without warming cards. Cards set at 38 degrees C or 42 degrees C raised the temperature in the medium to maxima of 34.5 degrees C and 37.5 degrees C respectively. Units were switched on daily for three one-hour periods. Cell numbers were counted by haemocytometer. RESULTS Maximum stimulation of endothelial cell proliferation occurred under the 38 degrees C card, with cells numbering 135-158% of the controls (p < 0.05). the 42 degrees C card also stimulated cells (110-155%) but this did not reach statistical significance. CONCLUSION The accelerated proliferation of microvascular dermal endothelial cells achieved by intermittent radiant warming may have contributed to the increase in granulation tissue reported previously in our clinic.
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Tang C, Nuruzzaman M, Rengel Z. Screening wheat genotypes for tolerance of soil acidity. ACTA ACUST UNITED AC 2003. [DOI: 10.1071/ar02116] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A soil-based screening method was used to test tolerance of wheat genotypes to acidity. Plants were grown for 6 days in an acid soil with the pH adjusted to 3.9–5.8. The number and length of roots were measured. To validate the method, 12 wheat cultivars of known acidity tolerance and one acid-sensitive barley cultivar were grown on an acid soil in the field with or without amelioration of subsoil acidity. The relative yields of these wheat genotypes on the soil with subsoil acidity ranged from 50 to 89% of yields on soil without subsoil acidity, and were correlated with root growth parameters obtained in the glasshouse. The best correlation was obtained between relative yields in the field (y) and root length per plant (x) at pH 3.9 in the glasshouse (y = –43 + 52*log x, r = 0.95) or root length per plant at pH 3.9 as a percentage of root length at pH 4.8 (y = 1.2 + 46*log x, r = 0.94). Following validation of the glasshouse screening method in the field, 115 wheat genotypes, including cultivars and breeding lines, were screened in the glasshouse. A substantial genotypic variation in acidity tolerance was found, with root length per plant at pH 3.9 ranging from 66 to > 350 mm. Many Western Australian breeding lines displayed better tolerance than existing tolerant wheat cultivars. The screening system can be instrumental in breeding wheat for increased tolerance to acid soils.
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Zhang B, Tang C, Jiang Z, Qi Y, Pang Y, Du J. Effects of adrenomedullin on vascular calcification in rats. ACTA ACUST UNITED AC 2002; 91:568-74. [PMID: 12242953 DOI: 10.1007/s00392-002-0815-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
OBJECTIVE The aim of the present study was to investigate the effect of adrenomedullin (ADM) on vascular calcification. METHODS The vascular calcification model was established in rats (VND group) by using vitamin D3 (300,000 IU/kg) and nicotine (25 mg/kg, two doses). The effect of liposome-encapsulated ADM was observed. Vascular calcium content, alkaline phosphatase (ALP) activity, ADM in aortic tissue and plasma, binding ability of 125I-ADM for ADM receptor on vascular plasma membrane and content of cAMP in vessels were measured. RESULTS Compared with control rats, the aortic calcium content and vascular ALP activity in rats of the VDN group was obviously increased; in addition ADM concentrations in plasma and vessels of rats in VDN group were increased. But the maximum binding sites of 125I-ADM for ADM receptor (Bmax) on vascular plasma membrane in rats of VDN group were significantly decreased compared with control rats. The affinity of 125I-ADM for the ADM receptor was reduced, as shown by the Kd value and vascular cAMP content being reduced in rats of the VDN group compared to the control group. The in vitro response of isolated vessels to ADM incubation was weakened. Administration of empty liposome had no effect on vascular calcification. But administration of ADM significantly decreased vascular calcium content and ALP activity. The Bmax of 125I-ADM for ADM receptors on vascular plasma membrane increased by 17.7% (p < 0.01), and the value of Kd decreased by 36.2% (P < 0.01) in rats treated with ADM as compared with rats of the VDN group. In addition, the vascular cAMP content and the response to ADM in isolated aorta were markedly increased. CONCLUSION Vascular calcification induced an alteration of the vascular ADM-ADM receptor-cAMP pathway. Treatment with exogenous ADM inhibited vascular calcification by improving the vascular ADM-ADM receptor-cAMP pathway.
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Cernik R, Bushnell-Wye G, Tang C, Dent A, Terril N, Diakun G, Barnes P, Greaves GN, Rayment T, Ryan A. A new facility for the study of materials processing on the SRS, Daresbury. Acta Crystallogr A 2002. [DOI: 10.1107/s0108767302087718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Feng G, Zhang FS, Li XL, Tian CY, Tang C, Rengel Z. Improved tolerance of maize plants to salt stress by arbuscular mycorrhiza is related to higher accumulation of soluble sugars in roots. MYCORRHIZA 2002; 12:185-90. [PMID: 12189473 DOI: 10.1007/s00572-002-0170-0] [Citation(s) in RCA: 123] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2001] [Accepted: 02/21/2002] [Indexed: 05/19/2023]
Abstract
The effect of colonization with the arbuscular mycorrhizal (AM) fungus Glomus mosseae (Nicol. & Gerd.) Gerdemann & Trappe on the growth and physiology of NaCl-stressed maize plants ( Zea mays L. cv. Yedan 13) was examined in the greenhouse. Maize plants were grown in sand with 0 or 100 mM NaCl and at two phosphorus (P) (0.05 and 0.1 mM) levels for 34 days, following 34 days of non-saline pre-treatment. Mycorrhizal plants maintained higher root and shoot dry weights. Concentrations of chlorophyll, P and soluble sugars were higher than in non-mycorrhizal plants under given NaCl and P levels. Sodium concentration in roots or shoots was similar in mycorrhizal and non-mycorrhizal plants. Mycorrhizal plants had higher electrolyte concentrations in roots and lower electrolyte leakage from roots than non-mycorrhizal plants under given NaCl and P levels. Although plants in the low P plus AM fungus treatment and those with high P minus AM fungus had similar P concentrations, the mycorrhizal plants still had higher dry weights, soluble sugars and electrolyte concentrations in roots. Similar relationships were observed regardless of the presence or absence of salt stress. Higher soluble sugars and electrolyte concentrations in mycorrhizal plants suggested a higher osmoregulating capacity of these plants. Alleviation of salt stress of a host plant by AM colonization appears not to be a specific effect. Furthermore, higher requirement for carbohydrates by AM fungi induces higher soluble sugar accumulation in host root tissues, which is independent of improvement in plant P status and enhances resistance to salt-induced osmotic stress in the mycorrhizal plant.
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Xu C, Tang C. [Discrimination of black inks by FT-Raman spectrometry]. FA YI XUE ZA ZHI 2002; 14:146-8, 191. [PMID: 11938888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
Six brands of black inks on paper were examined by FT-Raman spectrometry. The results showed that the black inks could be discriminated by FT-Raman spectrometry. As the method is easy, quick and undestructive to samples, it is useful in black ink examination.
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Eisenmenger W, Du XX, Tang C, Zhao S, Wang Y, Rong F, Dai D, Guan M, Qi A. The first clinical results of "wide-focus and low-pressure" ESWL. ULTRASOUND IN MEDICINE & BIOLOGY 2002; 28:769-774. [PMID: 12113789 DOI: 10.1016/s0301-5629(02)00507-0] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A clinical study of the concept "wide-focus and low-pressure" extracorporal shock-wave lithotripsy (ESWL) was performed in a scientific cooperation between the Physical Institute of the University of Stuttgart and the Xixin Medical Instruments Co. Ltd. in Wuxian-Suzhou, China. In this cooperation, self-focusing electromagnetic shock-wave generator systems from the University of Stuttgart were integrated into Xixin lithotripters and installed in seven hospitals in China. A total of 297 detailed patient protocols revealed an average of 1532 shock pulses for successful treatment with no necessity for pain medication and auxiliary measures, and a stone-free rate of 86% after a follow-up of 3 months. These results are discussed in terms of the wide-focus low-pressure conditions and the mechanism of binary fragmentation by squeezing.
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Lin DP, Falkenberg C, Payne DA, Thakkar J, Tang C, Elly C. Kinetics of purging for the priority volatile organic compounds in water. Anal Chem 2002. [DOI: 10.1021/ac00056a009] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Prueksaritanont T, Meng Y, Ma B, Leppert P, Hochman J, Tang C, Perkins J, Zrada M, Meissner R, Duggan ME, Lin JH. Differences in the absorption, metabolism and biliary excretion of a diastereomeric pair of alphavbeta3-antagonists in rat: limited role of P-glycoprotein. Xenobiotica 2002; 32:207-20. [PMID: 11958560 DOI: 10.1080/00498250110094403] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
1. The study investigated mechanisms underlying the pharmacokinetic differences of two zwitterionic diastereomers ((3S)-3-[(3R or 3S)-2-oxo-3-[3-(5,6,7,8-tetrahydro-1,8-naphthyridin-2-yl)propyl]pyrrolidin-1-yl]-3-quinolin-3-ylpropanoic acid) with different lipophilicities using a combination of in vivo and in vitro approaches. 2. In rat, both isomers possessed comparable plasma clearances (CL). However, the more lipophilic diastereomer I exhibited a higher metabolic clearance (>2-fold higher than II), whereas the hydrophilic zwitterion II exhibited a higher biliary clearance (approximately 5-fold higher than I). Following oral administration, the bioavailability (F) of I (17%) was much higher than that of II (1%). 3. Consistent with these in vivo observations and the expectation based on their lipophilicity differences, the metabolism in rat liver microsomes was faster and the permeability in Caco-2 and LLC-PK1 cells and in situ rat intestinal loop was better for I than for II. 4. Only the absorption of the more lipophilic diastereomer I was subjected to an efflux system in the Caco-2 and in situ rat intestinal loop models. I was a good substrate for P-glycoprotein (P-gp) in both the human MDR1 and mouse mdr1a transfected cell lines, and in the wild-type mdr1a (-/-) mouse when compared with the P-gp-deficient mdr1a (-/-) mouse. Concomitant administration of I with verapamil in rat caused significant increases in oral AUC, F and Cmax of I without affecting its CL, further supporting the effect of P-gp in limiting the intestinal absorption of I in vivo in this animal model. 5. Since the findings that the lipophilic diastereomer I, but not II, was a good P-gp substrate were not in line with the observations that I was excreted to bile much slower than II and that I was absorbed better than II, the results suggested that P-gp played a minor role to the observed differences in the biliary excretion and intestinal absorption of the diastereomers I and II in rat.
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Helling R, Li H, Mélin R, Miller J, Wingreen N, Zeng C, Tang C. The designability of protein structures. J Mol Graph Model 2002; 19:157-67. [PMID: 11381527 DOI: 10.1016/s1093-3263(00)00137-6] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
It has been noted that natural proteins adapt only a limited number of folds. Several researchers have investigated why and how nature has selected this small number of folds. Using simple models of protein folding, we demonstrate systematically that there is a "designability principle" behind nature's selection of protein folds. The designability of a structure (fold) is measured by the number of sequences that can design the structure--that is, sequences that possess the structure as their unique ground state. Structures differ drastically in terms of their designability. A small number of highly designable structures emerge with a number of associated sequences much larger than the average. These highly designable structures possess proteinlike secondary structures, motifs, and even tertiary symmetries. In addition, they are thermodynamically more stable and fold faster than other structures. These results suggest that protein structures are selected in nature because they are readily designed and stable against mutations, and that such a selection simultaneously leads to thermodynamic stability.
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Chen Y, Zhao M, Liu X, Yao W, Yang J, Zhang Z, Tang C. Urotensin II receptor in the rat airway smooth muscle and its effect on the rat airway smooth muscle cells proliferation. CHINESE MEDICAL SCIENCES JOURNAL = CHUNG-KUO I HSUEH K'O HSUEH TSA CHIH 2001; 16:231-5. [PMID: 12903763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Abstract
OBJECTIVE To investigate the characteristics of urotensin II (U-II) receptor in the rat airway smooth muscle and the effect and signal transduction pathway of U-II on the proliferation of airway smooth muscle cells. METHODS Using 125I-UII binding assay to measure the Bmax and Kd of U-II receptor. Using the 3H-TdR incorporation to determine the effect of U-II on the proliferation of airway smooth muscle cells and its signal transduction pathway. Using Fura-2/AM to measure the effect of U-1I on the cytosolic free calcium concentration. RESULTS 1. 125I-UII binding increased with the time and reached saturation at 45 min. The B(max0 was (11.36 +/- 0.37)fmol/mg pr and Kd was (4.46 +/- 0.61) nmol/L. 2. U-II increased 3H-TdR incorporation of the airway smooth muscle cells in a dose-dependent manner. 3. H7, PD98059 and nicardipine, inhibitors of PKC, MAPK, calcium channel, respectively, significantly inhibited U-II-stimulated 3H-TdR incorporation of airway smooth muscle cells. W7, inhibitor of CaM-PK, had no effect. 4. Cyclosporin A, inhibitor of CaN, inhibited 3H-TdR incorporation of the airway smooth muscle cells induced by U-II in a dose-dependent manner. 5. U-II promoted cytosolic free calcium concentration increase by 18%. CONCLUSIONS 1. There was U-II receptor in the rat airway smooth muscle. 2. The effect of U-II-stimulated 3H-TdR incorporation of airway smooth muscle cells was mediated by such signal transduction pathway as Ca2+, PKC, MAPK and CaN, etc.
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Tang C, Roidis N, Itamura J, Vaishnau S, Shean C, Stevanovic M. The effect of simulated elbow arthrodesis on the ability to perform activities of daily living. J Hand Surg Am 2001; 26:1146-50. [PMID: 11721267 DOI: 10.1053/jhsu.2001.28940] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The dominant elbow joint of 24 healthy volunteers was immobilized with a functional brace in increments of 20 degrees (6 positions ranging from 30 degrees to 130 degrees ). Average scores were obtained for personal care hygiene tasks (PCH), activity of daily living (ADL), and total functional scores (PCH + ADL) for each elbow flexion position. Functional scores increased with increasing elbow flexion, peaking at 110 degrees and then tapering down. Repeated-measures analysis of variance showed statistical significance, with functional scores improving with increasing elbow flexion for PCH, ADL, and PCH + ADL scores. Further pairwise comparisons for elbow position between 90 degrees and 110 degrees flexion groups demonstrated significant higher mean functional scores for ADL and combined PCH + ADL for the 110 degrees group. The results of this study support a clear advantage in subjects' upper-extremity functional abilities with the elbow immobilized at 110 degrees of flexion when dealing with normal upper-extremity joints. This angle of flexion should be considered in patients undergoing trial immobilization before an elbow arthrodesis.
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Yuan J, Gao R, Shi R, Song L, Tang J, Li Y, Tang C, Meng L, Yuan W, Chen Z. Intravascular local gene transfer mediated by protein-coated metallic stent. Chin Med J (Engl) 2001; 114:1043-5. [PMID: 11677763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023] Open
Abstract
OBJECTIVE To assess the feasibility, efficiency and selectivity of adenovirus-mediated gene transfer to local arterial wall by protein-coated metallic stent. METHODS A replication-defective recombinant adenovirus carrying the Lac Z reporter gene for nuclear-specific beta-galactosidase (Ad-beta gal) was used in this study. The coating for metallic stent was made by immersing it in a gelatin solution containing crosslinker. The coated stents were mounted on a 4.0 or 3.0 mm percutaneous transluminal coronary angioplasty (PTCA) balloon and submersed into a high-titer Ad-beta gal viral stock (2 x 10(10) pfu/ml) for 3 min, and then implanted into the carotid arteries in 4 mini-swines and into the left anterior descending branch of the coronary artery in 2 mini-swines via 8F large lumen guiding catheters. The animals were sacrificed 7 (n = 4), 14 (n = 1) and 21 (n = 1) days after implantation, respectively. The beta-galactosidase expression was assessed by X-gal staining. RESULTS The results showed that the expression of transgene was detected in all animal. In 1 of carotid artery with an intact intima, the beta-gal expression was limited to endothelial cells. In vessels with denuded endothelium, gene expression was found in the sub-intima, media and adventitia. The transfection efficiency of medial smooth muscle cells was 38.6%. In 2 animals sacrificed 7 days after transfection, a microscopic examination of X-gal-stained samples did not show evidence of transfection in remote organs and arterial segments adjacent to the treated arterial site. CONCLUSIONS Adenovirus-mediated arterial gene transfer to endothelial, smooth muscle cells and adventitia by protein-coated metallic stent is feasible. The transfection efficiency is higher. The coated stent may act as a good carrier of adenovirus-mediated gene transfer and have a potential to prevent restenosis following PTCA.
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Zhou H, Yang H, Tang C, Liu G, Pan Z. [The 5-year death analysis in patients with nasopharyngeal carcinoma treated with radiotherapy]. LIN CHUANG ER BI YAN HOU KE ZA ZHI = JOURNAL OF CLINICAL OTORHINOLARYNGOLOGY 2001; 15:458-9. [PMID: 12541692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVE To study the main death cause of nasopharyngeal carcinoma (NPC) treated with radiotherapy for 5 years. METHOD An analysis had been made to evaluated the 5-year death in 165 patients with NPC treated with radiotherapy. RESULT The death correlates strongly with the clinical stage, type and radiation dose (P < 0.05). CONCLUSION The distant metastasis and local recurrence are the main death cause of NPC.
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Wang C, Tang C, Tang L. [Inhibition effects of octreotide on the growth of hepatocellular carcinoma in vitro and in vivo]. ZHONGHUA YI XUE ZA ZHI 2001; 81:1194-7. [PMID: 11769709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To investigate the effects of somatostatin analogue octreotide on the proliferation and apoptosis of human hepatocellular carcinoma (HCC) cell line as well as the growth of HCC xenografts in nude mice. METHODS The effects of octreotide on the proliferation and apoptosis of SMMC-7721 HCC cells was measured by 3H-thymidine incorporation into DNA and the TdT-mediated dUTP nick end labeling assay (TUNEL) or flow cytometric assay separately. Nude mice bearing xenografts of the cell line were treated with octreotide or saline as a control daily until eight weeks after tumor implantation. RESULTS Incubation with octreotide decreased 3H-thymidine incorporation into DNA of SMMC-7721 cells by approximately 50% at a concentration of 1 mumol/L. The inhibit effect of octreotide showed a concentration dependence. After 96 h incubation, total cell count was decreased 52.2% compared with control. When cells were treated by octreotide at 1 x 10(-6) mol/L for 24 hours, the apoptosis rates was (15.2 +/- 2.4)%. At necropsy, in mice given octreotide, the mean tumor weight were significantly lower than that of control group (0.27 +/- 0.05 vs 0.85 +/- 0.37, P < 0.01). The inhibition rate of tumor in vivo at 2 months was 68.2%. CONCLUSION Octreotide is effective in inhibiting growth of HCC both in vivo and in vitro significantly. The mechanisms of antineoplastic effect action may involved in inhibiting DNA synthesize and inducing apoptosis of tumor cells.
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Chiba M, Tang C, Neway WE, Williams TM, Desolms SJ, Dinsmore CJ, Wai JS, Lin JH. P450 interaction with farnesyl-protein transferase inhibitors metabolic stability, inhibitory potency, and P450 binding spectra in human liver microsomes. Biochem Pharmacol 2001; 62:773-6. [PMID: 11551523 DOI: 10.1016/s0006-2952(01)00724-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Methyl substitution at the 2-position of the imidazole ring greatly improved drug metabolism profiles, in human liver microsomes, of ras farnesyl-protein transferase inhibitor (FTI) candidates for drug development. Methyl substitution markedly reduced the P450 inhibitory potency of non-substituted FTIs for CYP3A4 (by a factor of 12-403) and 2C9 (by a factor of 4.2-28), while it had little effect on the CYP2D6 enzyme. An immunochemical inhibition study demonstrated that CYP3A4 plays a predominant role in the metabolism of both non-substituted and 2-methyl-substituted imidazole-containing FTI candidates. Very strong type II binding spectra with human liver microsomes were observed for all non-substituted FTIs, while methyl substitution markedly weakened type II spectra or shifted the type of spectra from II to I. This indicated that methyl substitution on the imidazole moiety interfered with the substrate-P450 heme interaction, likely due to a steric effect caused by the methyl group. A kinetics study revealed that the methyl substitution increased V(max) and K(m) values to the same extent. These studies suggested that the 2-methyl substitution on the imidazole ring improved its drug metabolism profile by reducing the potential to inhibit CYP3A4-mediated metabolism without affecting intrinsic metabolic clearance (V(max)/K(m)).
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Lin J, Blake M, Tang C, Zimmer D, Rustandi RR, Weber DJ, Carrier F. Inhibition of p53 transcriptional activity by the S100B calcium-binding protein. J Biol Chem 2001; 276:35037-41. [PMID: 11454863 DOI: 10.1074/jbc.m104379200] [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: 12/17/2022] Open
Abstract
The levels of S100 Ca(2+)-binding proteins correlate with the progression of certain tumors, but their role, if any, in carcinogenesis is still poorly understood. S100B protein associates with both the p53 oligomerization domain (residues 325-355) and the extreme C terminus of the tumor suppressor p53 (residues 367-392). Consequently, S100B inhibits p53 tetramer formation and p53 phosphorylation mediated by protein kinase C, on p53 C-terminal end. In this report, we show that the S100B protein decreases p53 DNA binding and transcriptional activity. The effect of S100B is reflected in vivo by a reduced accumulation of p53, p21, and MDM2 protein levels in co-transfection assays and in response to bleomycin. The S100B can still interact with p53 in the absence of p53 extreme C-terminal end and reduce the expression of p53 downstream effector genes. These data indicate that S100B does not require p53 extreme C-terminal end to inhibit p53 activity. Collectively, these findings imply that elevated levels of S100B in tumors such as astrocytomas and gliomas could inhibit p53 functions and contribute to cancer progression.
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Xia C, Huo Y, Yin H, Zhu G, Tang C. Interleukin 10 inhibits the rat VSMC proliferation and collagen secretion stimulated by angiotensin II. CHINESE MEDICAL SCIENCES JOURNAL = CHUNG-KUO I HSUEH K'O HSUEH TSA CHIH 2001; 16:125-8. [PMID: 12899322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/21/2023]
Abstract
OBJECTIVE To study the effect of interleukin 10 (IL-10) on the angiotensin II (AngII) stimulated rat VSMC proliferation and collagen secretion, and furthermore, explore its mechanism. METHODS On cultured VSMC of rat, 3H-thymine (3H-TdR) and 3H-proline incorporations were used to evaluate the DNA and collagen synthesis, respectively. Western blot and immunoprecipitation were applied to assay the expression and activity of focal adhesion kinase (FAK), respectively. RESULTS IL-10 (10(-8) approximately 10(-10) g/ml) inhibited the increase of 3H-TdR and 3H-proline incorporation as well as FAK activity, which was induced by 10(-7) mol/L AngII (P < 0.05 or P < 0.01). IL-10 also obviously downregulated the synthesis and secretion of collagen by AngII stimulated VSMC. But there was no difference in the protein expression of FAK among all the groups (P > 0.05). CONCLUSION IL-10 antagonizes the VSMC proliferation and collagen synthesis by regulating FAK activity stimulated by AngII.
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Shihabuddin L, Buchsbaum MS, Hazlett EA, Silverman J, New A, Brickman AM, Mitropoulou V, Nunn M, Fleischman MB, Tang C, Siever LJ. Striatal size and relative glucose metabolic rate in schizotypal personality disorder and schizophrenia. ARCHIVES OF GENERAL PSYCHIATRY 2001; 58:877-84. [PMID: 11545672 DOI: 10.1001/archpsyc.58.9.877] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
BACKGROUND Schizotypal personality disorder (SPD) shares social deficits and cognitive impairment with schizophrenia, but is not typically characterized by frank psychosis. Because striatal size and functional activity have both been shown to be associated with psychotic symptoms, we carried out the first study of SPD to assess the caudate and putamen for comparison with findings in schizophrenia. METHODS Patients with SPD (n = 16), schizophrenic patients (n = 42), and age- and sex-matched normal control subjects (n = 47) were assessed with magnetic resonance imaging. All of the patients with SPD and subsamples of the schizophrenic patients (n = 27) and control subjects (n = 32) were also assessed with positron emission tomography using fluorodeoxyglucose F-18. RESULTS The relative size of the putamen in controls was significantly larger than in patients with SPD and significantly smaller than in schizophrenic patients, while the relative size of the caudate was similar in all 3 groups. Compared with control values, relative glucose metabolic rate in the ventral putamen was significantly elevated in patients with SPD and reduced in schizophrenic patients. When subsamples of schizophrenic patients (n = 10) and patients with SPD (n = 10) both of whom never received medication were compared, this pattern was more marked, with the highest value for the putamen being found in patients with SPD for the ventral slice and the lowest value for the right dorsal putamen. CONCLUSIONS Patients with SPD showed reduced volume and elevated relative glucose metabolic rate of the putamen compared with both schizophrenic patients and controls. These alterations in volume and activity may be related to the sparing of patients with SPD from frank psychosis.
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Qi J, Du J, Wang L, Zhao B, Tang C. Alleviation of hypoxic pulmonary vascular structural remodeling by L-arginine. Chin Med J (Engl) 2001; 114:933-6. [PMID: 11780385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
OBJECTIVE To explore the effect of L-arginine on hypoxic pulmonary vascular structural remodeling and its possible mechanisms. METHODS Eighteen Wistar rats were randomly divided into three groups: the hypoxia group, the hypoxia with L-arginine group and the control group. Pulmonary artery mean pressure was evaluated with right cardiac catheterization. Pulmonary vascular structural changes were also observed. Plasma concentration of nitric oxide (NO) was measured via spectrophotometry, and endothelin-1 (ET-1) mRNA expression in pulmonary artery endothelial cells was detected using in situ hybridization. RESULTS The pulmonary artery mean pressure was significantly high in hypoxic rats than in normal controls (20.33 +/- 2.18 mm Hg vs 15.38 +/- 1.05 mm Hg, P < 0.05). Microstructural and ultrastructural analysis revealed the development of hypoxic pulmonary vascular structural remodeling in the hypoxic rats. Meanwhile, the plasma NO concentration was markedly lower in the hypoxic rats than in controls (P < 0.05). The expression signals of ET-1 mRNA by pulmonary artery endothelial cells of hypoxic rats strengthened obviously. L-arginine ameliorated pulmonary hypertension (16.73 +/- 1.35 mm Hg vs 20.33 +/- 2.18 mm Hg, P < 0.05) as well as pulmonary vascular structural remodeling in the hypoxic rats in association with an increase in plasma NO concentration (P < 0.05) and inhibited ET-1 mRNA expression by the endothelial cells of pulmonary arteries. CONCLUSION L-arginine might play an important role in the regulation of hypoxic pulmonary vascular structural remodeling and hypoxic pulmonary hypertension. The mechanism is probably related to promoting NO production and, as a result, inhibiting ET-1 mRNA expression by pulmonary artery endothelial cells in hypoxic rats.
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Tang C, Klinman JP. The catalytic function of bovine lysyl oxidase in the absence of copper. J Biol Chem 2001; 276:30575-8. [PMID: 11395477 DOI: 10.1074/jbc.c100138200] [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: 11/06/2022] Open
Abstract
Bovine lysyl oxidase (BLO) contains two different cofactors, copper (Kagan, H. M. (1986) in Biology of Extracellular Matrix (Mecham, R. P., ed) Vol. 1, pp. 321-398, Academic Press, Orlando, FL) and lysine tyrosyl quinone (LTQ) (Wang, S. X., Mure, M., Medzihradszky, K. F., Burlingame, A. L., Brown, D. E., Dooley, D. M., Smith, A. J., Kagan, H. M., and Klinman, J. P. (1996) Science 273, 1078-1084). By a combination of UV-visible spectroscopy, metal content analysis, and activity measurements, we find that copper-depleted BLO reacts in an irreversible manner with phenylhydrazine, an amine substrate analog, and catalyzes multiple turnovers of the substrate benzylamine. After removal of the majority of enzyme-bound copper, apoBLO exhibits a decrease in the LTQ content, as evidenced by the drop of the 510-520-nm absorbance, suggesting that the copper may play a structural role in stabilizing the LTQ. The remaining intact LTQ in the apoBLO reacted with phenylhydrazine, both in the presence and absence of the chelator, 10 mm 2,2'-dipyridyl. When benzylamine was used as the substrate, the apoBLO turned over at a rate of 50-60% of the native BLO (after correction for the residual copper and the change of LTQ content). Copper contamination from the assay buffer was ruled out by comparison of enzyme activity using different apoBLO concentrations. These studies demonstrate that the mature form of lysyl oxidase retains many of its functions in the absence of copper.
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Lane ME, Yu B, Rice A, Lipson KE, Liang C, Sun L, Tang C, McMahon G, Pestell RG, Wadler S. A novel cdk2-selective inhibitor, SU9516, induces apoptosis in colon carcinoma cells. Cancer Res 2001; 61:6170-7. [PMID: 11507069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Recent studies have indicated that the development of cyclin-dependent kinase (cdk)2 inhibitors that deregulate E2F are a plausible pharmacological strategy for novel antineoplastic agents. We show here that 3-[1-(3H-Imidazol-4-yl)-meth-(Z)-ylidene]-5-methoxy-1,3-dihydro-indol-2-one (SU9516), a novel 3-substituted indolinone compound, binds to and selectively inhibits the activity of cdk2. This inhibition results in a time-dependent decrease (4-64%) in the phosphorylation of the retinoblastoma protein pRb, an increase in caspase-3 activation (5-84%), and alterations in cell cycle resulting in either a G(0)-G(1) or a G(2)-M block. We also report here cell line differences in the cdk-dependent phosphorylation of pRb. These findings demonstrate that SU9516 is a selective cdk2 inhibitor and support the theory that compounds that inhibit cdk2 are viable resources in the development of new antineoplastic agents.
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Wu LL, Tang C, Liu MS. Altered phosphorylation and calcium sensitivity of cardiac myofibrillar proteins during sepsis. Am J Physiol Regul Integr Comp Physiol 2001; 281:R408-16. [PMID: 11448842 DOI: 10.1152/ajpregu.2001.281.2.r408] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Altered phosphorylation and Ca(2+) sensitivity of cardiac myofibrillar proteins during different phases of sepsis were investigated. Sepsis was induced by cecal ligation and puncture (CLP). The results show that phosphorylation of troponin I (TnI) was increased by 268% during the early phase (9 h after CLP) but decreased by 46% during the late phase (18 h after CLP) of sepsis. Phosphorylation of C protein was increased by 76% during the early phase but decreased by 41% during the late phase of sepsis. Phosphorylation of myosin light chain-2 (MLC-2) remained unaltered during the early phase but was decreased by 38% during the late phase of sepsis. Phosphorylation of TnT was unaffected during the progression of sepsis. The increases in the phosphorylation of TnI and C protein during early sepsis were associated with the decrease in the Ca(2+) sensitivity of myofilaments and the increases in myocardial changes in tension development (+dP/dt(max)) and cAMP level. The decreases in the phosphorylation of TnI and C protein during late sepsis coincided with the declines in the activities of myofibrillar ATPase, Ca(2+) sensitivity of myofilaments, myocardial +/-dP/dt(max), and cAMP content. The increases and the decreases in the phosphorylation of TnI and C protein, +/-dP/dt(max), and the tissue cAMP level were sensitive to isoproterenol stimulation and propranolol inhibition. These findings suggest that alterations in the phosphorylation of myofibrillar proteins, such as TnI, C protein, and MLC-2, and changes in the activities and the Ca(2+) sensitivity of myofibrillar ATPase may contribute to the altered cardiac function during the progression of sepsis. Furthermore, the sepsis-induced alterations in the phosphorylation and Ca(2+) sensitivity of cardiac myofibrillar proteins were mediated via a beta-adrenergic receptor pathway.
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Chen G, Liu N, Zhou A, Tang C, Ma D, Tang J. The role of hypertension-related gene in aortic vascular smooth muscle cells from mice and rats. Chin Med J (Engl) 2001; 114:833-6. [PMID: 11780361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
OBJECTIVE To study the role of hypertension-related gene (HRG-1) in cardiovascular disease. METHODS The expression of HRG-1 was analyzed with RT-PCR and Northern blotting. Vascular smooth muscle cell (VSMC) proliferation was measured with 3H-TdR incorporation and was confirmed with histological analysis. RESULTS Northern blot analysis showed that HRG-1 mRNA was expressed not only in VSMC, but also in various rat tissues (heart, brain, lung, kidney, and liver). In addition, the expression of HRG-1 mRNA in heart, brain, kidney and liver of spontaneously hypertensive rat (SHR) was lower than that in the same tissues of Wistar-Kyotorat (WKY). Semi-quantitative RT-PCR and histological analysis showed that the expression of HRG-1 mRNA in ApoE-knockout mice and in animal models of restenosis was decreased and neointimal formation was observed in both models. ET, AII, and IL-1 stimulating VSMC proliferation reduced the expression of HRG-1 mRNA of VSMC. Atrial natriuretic factor (ANF), calcitonin gene-related peptide and adrenomedullin, inhibited VSMC proliferation and elevated the expression of HRG-1 mRNA. These effects could be blocked or attenuated by their corresponding antagonists or antibodies. CONCLUSION HRG-1 is a gene related to VSMC proliferation. It may play an important role in several occlusive cardiovascular diseases including atherosclerosis, restenosis and hypertension.
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Li W, Wu Y, Cai S, Tang C. [Comparative effects of decreasing viscosity in different preparations of Chinese angelica root and ginseng]. ZHONG YAO CAI = ZHONGYAOCAI = JOURNAL OF CHINESE MEDICINAL MATERIALS 2001; 24:581-3. [PMID: 11715197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
OBJECTIVE To compare the effects of different preparations of Chinese angilica root and ginseng on decreasing whole blood viscosity and plasma viscosity in rats. METHOD The hemorheological method was used in vivo or in vitro and a Decreasing Viscosity Index (DIV) was defined as a comparative scalar. RESULTS In the effect of the groups of Chinese angilica root on decreasing viscosity, the effect of whole root group was the best and the effect of main root group was better than that of the tributary root group. Meanwhile the same effect of transplant wild ginseng group was greater than that of dried raw ginseng group. CONCLUSION This work provided some fundamental evidences for clinical application and pharmacological data for the quality evaluation.
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Hochman JH, Chiba M, Yamazaki M, Tang C, Lin JH. P-glycoprotein-mediated efflux of indinavir metabolites in Caco-2 cells expressing cytochrome P450 3A4. J Pharmacol Exp Ther 2001; 298:323-30. [PMID: 11408558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023] Open
Abstract
The role of P-glycoprotein in secretion of indinavir metabolites produced by CYP3A4 was evaluated in Caco-2 cells expressing CYP3A4. Metabolism of indinavir by CYP3A4 expressing Caco-2 cells grown on filters resulted in the formation of N-dealkylation products (M5 and M6) and hydroxylation of indinavir, which were preferentially secreted into the apical compartment. Apical secretion of the metabolites was inhibited by cyclosporin A (CsA) with all three classes of metabolites showing similar sensitivity to CsA, suggesting that they are all secreted by the same pathway. M6 stimulated P-glycoprotein (Pgp)-ATPase activity in a concentration-dependent manner. This stimulation was inhibited by the Pgp-specific monoclonal antibody C219. A method was developed to specifically inhibit Pgp using the monoclonal antibody UIC2 to determine whether Pgp efflux accounts for a significant proportion of the apical secretion of indinavir metabolites. UIC2 recognizes an extracellular transient conformational epitope that is stabilized by some Pgp substrates or by ATP depletion. Incubation of Caco-2 cells with UIC2 in the presence of 1 microM CsA resulted in 50 to 80% inhibition of Pgp-mediated vinblastine efflux, with no significant inhibition observed by UIC2 or CsA alone. Inhibition of Pgp in CYP3A4-expressing Caco-2 cells by UIC2 and 1 microM CsA resulted in a significant decrease in the apical secretion of M6, M5, and OH-indinavir and an increase in the amount of the metabolites secreted in the basolateral compartment and retained in the cytosol. These results are consistent with a role of Pgp in elimination of CYP3A4-generated metabolites and indicate that even relatively polar metabolites may be secreted from the cell by Pgp.
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Yang X, Wei LL, Tang C, Slack R, Mueller S, Lippman ME. Overexpression of KAI1 suppresses in vitro invasiveness and in vivo metastasis in breast cancer cells. Cancer Res 2001; 61:5284-8. [PMID: 11431371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
KAI1 is a metastasis suppressor gene for human prostate cancer and is also involved in the progression of a variety of other human cancers. Previously, we have demonstrated that KAI1 expression was down-regulated in metastatic breast cancer cell lines as well as in highly aggressive breast cancer specimens. To determine whether KAI1 expression is responsible for the metastasis suppression in breast cancer, we transfected the human KAI1 cDNA into two highly malignant breast cancer cell lines, LCC6 and MDA-MB-231, which both have low levels of endogenous KAI1 expression. Parental, vector-only transfectants and KAI1 transfectant clones were injected into the mammary fat pads and tail veins, respectively, of athymic nude mice and assessed for both spontaneous and experimental lung metastasis. High KAI1 expression significantly suppressed the metastatic potential of KAI1-transfected LCC6 cells. Metastasis suppression correlated with the reduced rate of tumor growth and a decreased clonogenicity in soft agar. Furthermore, KAI1 expression significantly suppressed the in vitro cell invasion in KAI1-transfected MDA-MB-231 cells. Our results suggested that KAI1 may function as a negative regulator of breast cancer metastasis.
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