151
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Li YH, Uberuaga BP, Jiang C, Choudhury S, Valdez JA, Patel MK, Won J, Wang YQ, Tang M, Safarik DJ, Byler DD, McClellan KJ, Usov IO, Hartmann T, Baldinozzi G, Sickafus KE. Role of antisite disorder on preamorphization swelling in titanate pyrochlores. Phys Rev Lett 2012; 108:195504. [PMID: 23003057 DOI: 10.1103/physrevlett.108.195504] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2011] [Indexed: 06/01/2023]
Abstract
Ion irradiation experiments and atomistic simulations were used to demonstrate that irradiation-induced lattice swelling in a complex oxide, Lu2Ti2O7, is due initially to the formation of cation antisite defects. X-ray diffraction revealed that cation antisite formation correlates directly with lattice swelling and indicates that the volume per antisite pair is approximately 12 Å3. First principles calculations revealed that lattice swelling is best explained by cation antisite defects. Temperature accelerated dynamics simulations indicate that cation Frenkel defects are metastable and decay to form antisite defects.
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Affiliation(s)
- Y H Li
- Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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Alcalay R, Rosado L, Mejia-Santana H, Orbe-Reilly M, Caccappolo E, Tang M, Ruiz D, Ross B, Verbitsky M, Kisselev S, Louis E, Comella C, Colcher A, Jennings D, Nance M, Bressman S, Scott W, Tanner C, Andrews H, Waters C, Fahn S, Cote L, Frucht S, Ford B, Rezak M, Novak K, Friedman J, Pfeiffer R, Marsh L, Hiner B, Siderowf A, Payami H, Molho E, Nutt J, Factor S, Ottman R, Clark L, Marder K. Clinical and Genetic Characteristics of Participants with Juvenile PD: The CORE-PD Study (IN10-2.001). Neurology 2012. [DOI: 10.1212/wnl.78.1_meetingabstracts.in10-2.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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153
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Alcalay R, Rosado L, Mejia-Santana H, Orbe-Reilly M, Caccappolo E, Tang M, Ruiz D, Ross B, Verbitsky M, Kisselev S, Louis E, Comella C, Colcher A, Jennings D, Nance M, Bressman S, Scott W, Tanner C, Andrews H, Waters C, Fahn S, Cote L, Frucht S, Ford B, Rezak M, Novak K, Friedman J, Pfeiffer R, Marsh L, Hiner B, Siderowf A, Payami H, Molho E, Nutt J, Factor S, Ottman R, Clark L, Marder K. Clinical and Genetic Characteristics of Participants with Juvenile PD: The CORE-PD Study (S42.002). Neurology 2012. [DOI: 10.1212/wnl.78.1_meetingabstracts.s42.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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154
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Caccappolo E, Alcalay R, Marder K, Tang M, Rosado L, Mejia-Santana H, Ruiz D, Orbe-Reilly M, Ross B, Verbitsky M, Kisselev S, Louis E, Colcher A, Comella C, Siderowf A, Jennings D, Nance M, Bressman S, Scott W, Tanner C, Mickel S, Waters C, Fahn S, Cote L, Frucht S, Ford B, Rezak M, Friedman J, Marsh L, Hiner B, Payami H, Molho E, Ottman R, Clark L. The Effect of Parkin Mutation Status on Cognitive Functioning in EOPD Patients with Long Disease Duration: The CORE-PD Study (PD7.008). Neurology 2012. [DOI: 10.1212/wnl.78.1_meetingabstracts.pd7.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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155
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Tester R, Al-Ghazzewi F, Shen N, Chen Z, Chen F, Yang J, Zhang D, Tang M. The use of konjac glucomannan hydrolysates to recover healthy microbiota in infected vaginas treated with an antifungal agent. Benef Microbes 2012; 3:61-6. [PMID: 22348910 DOI: 10.3920/bm2011.0021] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The aim of this study was to evaluate how konjac glucomannan hydrolysates (GMH) could support the healthy re-colonisation of vaginal microflora post infections. A total of 26 female patients (12 controls and 14 treatments) aged 18 to 25 suffering from vaginal infection were recruited for this study. Patients were assigned randomly into two groups to receive a standard antifungal treatment or a standard antifungal treatment plus pessary capsules containing 200 mg GMH (twice a week for thirty days). Patients were assessed on day zero, sixteen and thirty of the trial. Several parameters were determined including yeast and bacterial counts, the KOH test, pH, Gram staining and wet mount microscopic observations. The results showed that the counts of Candida were diminished completely with antifungal treatment for both groups. However, the total bacterial counts increased with time in the GMH pessary group unlike the control. The normalised average KOH scores were reduced sharply with time in both groups although in the control group scores started to increase after sixteen days. The normalised average white blood cell scores also decreased with time for both groups. Epithelial cell scores decreased only for the GMH pessary group while clue cells and yeast-like fungi decreased with time for both control and GMH pessary groups. These results indicate the improvement of vaginal health recovery (post antifungal treatment for Candida infection) and especially the presence of healthy microflora due to the introduction of GMH in the vagina. The data indicate that it would be worth examining further the health benefits of GMH in a vaginal health format with a view to employing the material as a prophylactic or therapeutic agent. It provides an alternative approach to reducing vaginal infections and promoting consumer health.
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Affiliation(s)
- R. Tester
- Glycologic Limited, 70 Cowcaddens Road, Glasgow G4 0BA, United Kingdom
| | - F. Al-Ghazzewi
- Glycologic Limited, 70 Cowcaddens Road, Glasgow G4 0BA, United Kingdom
| | - N. Shen
- Suining Chinese Medicine Hospital, 629000 Suining City, Sichuan, P.R. China
| | - Z. Chen
- Suining Chinese Medicine Hospital, 629000 Suining City, Sichuan, P.R. China
| | - F. Chen
- Suining Chinese Medicine Hospital, 629000 Suining City, Sichuan, P.R. China
| | - J. Yang
- Suining Chinese Medicine Hospital, 629000 Suining City, Sichuan, P.R. China
| | - D. Zhang
- Suining Chinese Medicine Hospital, 629000 Suining City, Sichuan, P.R. China
| | - M. Tang
- Glycologic Limited, 70 Cowcaddens Road, Glasgow G4 0BA, United Kingdom
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156
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Tan T, Ellis J, Koplin J, Martin P, Dang T, Matheson M, Dharmage S, Lowe A, Tang M, Robinson M, Ponsonby A, Osborne N, Hill D, Allen K. Filaggrin Mutations are Associated with an Increased Risk of Infantile Food Allergy and Sensitization. J Allergy Clin Immunol 2012. [DOI: 10.1016/j.jaci.2011.12.213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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157
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Erbas B, Akram M, Dharmage S, Tham R, Dennekamp M, Newbigin E, Taylor P, Tang M, Abramson M. The Role of Seasonal Grass Pollen on Childhood Asthma Emergency Department Presentations. J Allergy Clin Immunol 2012. [DOI: 10.1016/j.jaci.2011.12.382] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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158
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Dang T, Choo S, Licciardi P, Koplin J, Martin P, Tan T, Gurrin L, Tey D, Robinson M, Dharmage S, Tang M, Allen K. Increasing The Accuracy Of Peanut Allergy Diagnosis Using Ara H2. J Allergy Clin Immunol 2012. [DOI: 10.1016/j.jaci.2011.12.165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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159
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Tang M, Odejinmi SI, Vankayalapati H, Wierenga K, Lai K. Innovative therapy for Classic Galactosemia - tale of two HTS. Mol Genet Metab 2012; 105:44-55. [PMID: 22018723 PMCID: PMC3253915 DOI: 10.1016/j.ymgme.2011.09.028] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Revised: 09/21/2011] [Accepted: 09/21/2011] [Indexed: 01/04/2023]
Abstract
Classic Galactosemia is an autosomal recessive disorder caused by the deficiency of galactose-1-phosphate uridylyltransferase (GALT), one of the key enzymes in the Leloir pathway of galactose metabolism. While the neonatal morbidity and mortality of the disease are now mostly prevented by newborn screening and galactose restriction, long-term outcome for older children and adults with this disorder remains unsatisfactory. The pathophysiology of Classic Galactosemia is complex, but there is convincing evidence that galactose-1-phosphate (gal-1P) accumulation is a major, if not the sole pathogenic factor. Galactokinase (GALK) inhibition will eliminate the accumulation of gal-1P from both dietary sources and endogenous production, and efforts toward identification of therapeutic small molecule GALK inhibitors are reviewed in detail. Experimental and computational high-throughput screenings of compound libraries to identify GALK inhibitors have been conducted, and subsequent studies aimed to characterize, prioritize, as well as to optimize the identified positives have been implemented to improve the potency of promising compounds. Although none of the identified GALK inhibitors inhibits glucokinase and hexokinase, some of them cross-inhibit other related enzymes in the GHMP small molecule kinase superfamily. While this finding may render the on-going hit-to-lead process more challenging, there is growing evidence that such cross-inhibition could also lead to advances in antimicrobial and anti-cancer therapies.
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Affiliation(s)
- M Tang
- Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, Utah, U.S.A
| | - SI Odejinmi
- Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, Utah, U.S.A
| | - H Vankayalapati
- Center for Investigational Therapeutics, Huntsman Cancer Institute, The University of Utah, Salt Lake City, Utah, U.S.A
| | - K Wierenga
- Department of Pediatrics, Section of Genetics, OUHSC, Oklahoma City, Oklahoma, U.S.A
- Corresponding Authors: Kent Lai, Ph.D., Department of Pediatrics, Division of Medical Genetics, University of Utah School of Medicine, 50 N. Mario Capecchi Drive, SOM Room 2C412, Salt Lake City, UT 84132, U.S.A., (); KlaasWierenga, M.D., Department of Pediatrics, Section of Genetics, OUHSC, OUCP Suite 12100, Oklahoma City, OK 73104, U.S.A., ()
| | - K Lai
- Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, Utah, U.S.A
- Corresponding Authors: Kent Lai, Ph.D., Department of Pediatrics, Division of Medical Genetics, University of Utah School of Medicine, 50 N. Mario Capecchi Drive, SOM Room 2C412, Salt Lake City, UT 84132, U.S.A., (); KlaasWierenga, M.D., Department of Pediatrics, Section of Genetics, OUHSC, OUCP Suite 12100, Oklahoma City, OK 73104, U.S.A., ()
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160
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Tang M, Nielsen HHM, Lesbo M, Frokiaer J, Maagaard M, Pilegaard HK, Hjortdal VE. Improved cardiopulmonary exercise function after modified Nuss operation for pectus excavatum. Eur J Cardiothorac Surg 2011; 41:1063-7. [DOI: 10.1093/ejcts/ezr170] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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161
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Lesbo M, Tang M, Nielsen HH, Frokiaer J, Lundorf E, Pilegaard HK, Hjortdal VE. Compromised cardiac function in exercising teenagers with pectus excavatum. Interact Cardiovasc Thorac Surg 2011; 13:377-80. [DOI: 10.1510/icvts.2011.267054] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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162
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Tang M, Odejinmi SI, Allette YM, Vankayalapati H, Lai K. Identification of novel small molecule inhibitors of 4-diphosphocytidyl-2-C-methyl-D-erythritol (CDP-ME) kinase of Gram-negative bacteria. Bioorg Med Chem 2011; 19:5886-95. [PMID: 21903402 DOI: 10.1016/j.bmc.2011.08.012] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2011] [Revised: 08/02/2011] [Accepted: 08/08/2011] [Indexed: 11/17/2022]
Abstract
The biosyntheses of isoprenoids is essential for the survival in all living organisms, and requires one of the two biochemical pathways: (a) Mevalonate (MVA) Pathway or (b) Methylerythritol Phosphate (MEP) Pathway. The latter pathway, which is used by all Gram-negative bacteria, some Gram-positive bacteria and a few apicomplexan protozoa, provides an attractive target for the development of new antimicrobials because of its absence in humans. In this report, we describe two different approaches that we used to identify novel small molecule inhibitors of Escherichia coli and Yersinia pestis 4-diphosphocytidyl-2-C-methyl D-erythritol (CDP-ME) kinases, key enzymes of the MEP pathway encoded by the E. coli ispE and Y. pestisipk genes, respectively. In the first approach, we explored existing inhibitors of the GHMP kinases while in the second approach; we performed computational high-throughput screening of compound libraries by targeting the CDP-ME binding site of the two bacterial enzymes. From the first approach, we identified two compounds with 6-(benzylthio)-2-(2-hydroxyphenyl)-4-oxo-3,4-dihydro-2H-1,3-thiazine-5-carbonitrile and (Z)-3-methyl-4-((5-phenylfuran-2-yl)methylene)isoxazol-5(4H)-one scaffolds which inhibited E. coli CDP-ME kinase in vitro. We then performed substructure search and docking experiments based on these two scaffolds and identified twenty three analogs for structure-activity relationship (SAR) studies. Three new compounds from the isoxazol-5(4H)-one series have shown inhibitory activities against E. coli and Y. pestis CDP-ME kinases with the IC(50) values ranging from 7 to 13 μM. The second approach by computational high-throughput screening (HTS) of two million drug-like compounds yielded two compounds with benzenesulfonamide and acetamide moieties which, at a concentration of 20 μM, inhibited 80% and 65%, respectively, of control CDP-ME kinase activity.
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Affiliation(s)
- M Tang
- Division of Medical Genetics, Department of Pediatrics, University of Utah School of Medicine, 50 N. Mario Capecchi Drive, SOM Room 2C412, Salt Lake City, UT 84132, USA
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Ng B, Hanham SM, Giannini V, Chen ZC, Tang M, Liew YF, Klein N, Hong MH, Maier SA. Lattice resonances in antenna arrays for liquid sensing in the terahertz regime. Opt Express 2011; 19:14653-14661. [PMID: 21934827 DOI: 10.1364/oe.19.014653] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Terahertz antenna arrays supporting narrow lattice resonances are proposed as an alternative sensor-on-chip approach to liquid sensing. An array of metallic rectangular antennas fabricated on a polyethylene naphthalate (PEN) substrate is used to demonstrate the sensing of a number of fluids. Good agreement is shown between experiment and simulation with Q-factors of around 20 and a figure-of-merit (FOM) of 3.80 being achieved. Liquid sensing with antenna arrays is simple both in terms of fabrication and setup. The working frequency can be tuned with a suitable choice of substrates and array parameters. The nature of the lattice resonance means that the whole sample is used to provide the conditions required for resonance occurrence, eliminating the need to preferentially locate the sample in small areas of high field concentration. The antenna arrays could also potentially be coupled with a microfluidic system for in situ sensing or used in a reflection setup.
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Affiliation(s)
- B Ng
- Experimental Solid State Goup, Physics Department, Imperial College London, London SW72AZ, UK.
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164
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Tang M, Chang ST, Huang CX, Liu YT, Chen YH. Impact of the nanorod structure on the tandem thin-film solar cell. J Nanosci Nanotechnol 2011; 11:5728-5732. [PMID: 22121598 DOI: 10.1166/jnn.2011.4353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The novel thin-film solar cell was investigated with a nanorod structure that could solve the conflict between light absorption and carrier transport in the amorphous silicon (a-Si)/amorphous silicon-germanium (a-SiGe) tandem thin-film solar cell. This structure has an n-type a-Si nanorod array on the substrate, and an a-SiOx p-layer and an a-SiGe i-layer are sequentially grown along the surface of each n-type a-Si nanorod, for the bottom cell. After the above bottom-cell process, a similar process is used to fabricate an amorphous Si p-i-n top cell on the bottom cell. Under sunlight illumination, the light is absorbed along the vertical direction of the nanorod, but as the carrier transport is along the horizontal direction, the nanorod may absorb most of the sunlight. In the meantime, the solar cell is still thin enough for the effective transport of photogenerated carriers.
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Affiliation(s)
- M Tang
- Department of E. E., National Chung Hsing University, Taichung, 402, Taiwan, R.O.C
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165
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Wang YY, Notake T, Tang M, Nawata K, Ito H, Minamide H. Terahertz-wave water concentration and distribution measurement in thin biotissue based on a novel sample preparation. Phys Med Biol 2011; 56:4517-27. [PMID: 21719948 DOI: 10.1088/0031-9155/56/14/018] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The measurement of water concentration and distribution in thin biotissues with terahertz (THz)-wave has been proposed. In this paper, a novel sample preparation approach was introduced to effectively preserve tissue freshness at room temperature. Excellent stability of this method was demonstrated by measuring the transmittance spectroscopy and imaging many times within a certain time. Moreover, the reliability of water volume concentration measurement with THz-wave was evaluated. Measurement results using THz-wave were in good agreement with volume concentration measurement results based on other quantitative methods. The results suggest that water concentration and distribution measurement in thin biotissues using THz-wave will be a potential modality for medical and biological diagnosis.
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166
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Lin KG, Tang M, Guo YB, Han HY, Lin YH. Two polymorphisms of RCAN1 gene associated with Alzheimer's disease in the Chinese Han population. East Asian Arch Psychiatry 2011; 21:79-84. [PMID: 21838211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
OBJECTIVE Regulator of calcineurin 1 (RCAN1) gene is a regulator on the activity of calcineurin and was reported to be overexpressed in Alzheimer's disease. The aim of this study was to evaluate several polymorphisms of RCAN1, located in the probable promoter region of RCAN1-4 and around the exonic splicing enhancer motifs of RCAN1, in a cohort of Chinese late-onset Alzheimer's disease. METHODS A pilot case-control study was conducted in 142 Alzheimer's disease patients and 99 nondemented controls from Chinese Han population. Fragments of the RCAN1 including 5 polymorphisms (rs71324311, rs3831376, rs10550296, rs8135540, rs78899361) were amplified and sequenced. RESULTS In our sample, 2 polymorphisms (rs71324311 and rs10550296) were associated with Alzheimer's disease. Of these 2 polymorphisms, the heterozygous deletion genotype of rs71324311 was more prevalent in non-demented controls than in those with Alzheimer's disease (4% vs. 0%), indicating a slight protective role (Fisher's exact test, p = 0.03; crude odds ratio = 0.96, 95% confidence interval = 0.92-0.99). There was only a trend towards a significant difference in the distributions of genotypes of rs10550296 between 2 groups (chi2 = 1.93; p = 0.17; crude odds ratio = 1.44, 95% confidence interval = 0.85-2.41). However, logistic regression analysis showed that the age-, gender- and apolipoprotein E epsilon4-adjusted odds ratio of Alzheimer's disease with rs10550296 heterozygous deletion genotype was 2.11 (chi2 = 4.42; p = 0.04; 95% confidence interval = 1.05-4.20). CONCLUSIONS Regarding Alzheimer's disease susceptibility in Chinese Han population, our data suggested a protective role for the rs71324311 heterozygous deletion genotype and a risk role from the rs10550296 heterozygous deletion genotype.
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Affiliation(s)
- K G Lin
- Department of Geriatric Psychiatry, Guangzhou Psychiatric Hospital, Affiliated Hospital of Guangzhou Medical College, Guangdong Province 510370, PR China.
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De-jun Y, Shu-long Z, Dong C, Zhi-tao Z, Xian-jing W, Ying-xue D, Tang M, Ning XH, Tang Y, Tian Y, Zhang S, Qiao-yan B, Shu-long Z, Dong C, Zhi-tao Z, Xian-jing W, Ying-xue D, Zhou X, Guo LS, Cai J, Wei DM, Shi L, Yang G, Liu XQ, Yang XC, Ye Z, Yu-tang W, Zhao-liang S, Yuan G, Hong-yang G. Animal Models for Cardiac Arrhythmias. Europace 2011. [DOI: 10.1093/europace/euq473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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168
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Ismail I, Licciardi P, Oppedisano F, Donath S, Tang M. Prenatal Probiotic Supplementation is Associated with Reduced sCD14 and Total IgA in Breast Milk. J Allergy Clin Immunol 2011. [DOI: 10.1016/j.jaci.2010.12.152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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169
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Tang M, Wierenga K, Elsas LJ, Lai K. Molecular and biochemical characterization of human galactokinase and its small molecule inhibitors. Chem Biol Interact 2010; 188:376-85. [PMID: 20696150 DOI: 10.1016/j.cbi.2010.07.025] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2010] [Revised: 07/20/2010] [Accepted: 07/30/2010] [Indexed: 11/17/2022]
Abstract
Human galactokinase (GALK) is the first enzyme in the Leloir pathway, converting α-d-galactose into galactose-1-phosphate (Gal-1-P). Recently, there is increasing interest in targeting GALK as a novel therapy to ameliorate the disease manifestations in patients with Classic Galactosemia as it would, in combination with (ga-)lactose restriction reduce accumulation of Gal-1-P, a cytotoxic agent. Previously, we identified 34 small molecule compounds that inhibited GALK in vitro using experimental high-throughput screening. In order to isolate useful lead compounds, we characterized these hits with regards to their kinase selectivity profiles, potency and capability to reduce Gal-1-P accumulation in patient cell lines, and their modes of action. We found that the majority of these compounds had IC(50)s ranging from 0.7μM to 33.3μM. When tested against other members of the GHMP kinase family, three compounds (1, 4, and 24) selectively inhibited GALK with high potency. Through alignment of GALK and mevalonate kinase (MVK) crystal structures, we identified that eight amino acid residues and an L1 loop were different within the ATP-binding pockets of these two closely related kinases. By site-directed mutagenesis experiments, we identified one amino acid residue required for the inhibitory function of two of the three selective compounds. Based on these results, we generated binding models of these two compounds using a high-precision docking program. Compounds 4 and 24 inhibited GALK in a mixed model, while compound 1 exhibited parabolic competitive inhibition. Most importantly, using cells from galactosemic patients we found that selected compounds lowered Gal-1-P concentrations.
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Affiliation(s)
- M Tang
- Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, USA
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170
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Tang M, Holliday K, Jiang C, Valdez J, Uberuaga B, Dickerson P, Dickerson R, Wang Y, Czerwinski K, Sickafus K. Order-to-disorder phase transformation in ion irradiated uranium-bearing delta-phase oxides RE6U1O12 (RE=Y, Gd, Ho, Yb, and Lu). J SOLID STATE CHEM 2010. [DOI: 10.1016/j.jssc.2010.01.020] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Leung KY, Cheong KB, Lee CP, Chan V, Lam YH, Tang M. Ultrasonographic prediction of homozygous alpha0-thalassemia using placental thickness, fetal cardiothoracic ratio and middle cerebral artery Doppler: alone or in combination? Ultrasound Obstet Gynecol 2010; 35:149-154. [PMID: 20047196 DOI: 10.1002/uog.7443] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
OBJECTIVE To compare the predictive values of three ultrasonographic parameters: placental thickness (PT), fetal cardiothoracic ratio (CTR) and middle cerebral artery peak systolic velocity (MCA-PSV), alone or in combination, in pregnancies affected by homozygous alpha(0)-thalassemia at 12-20 weeks' gestation. METHODS Pregnant women at risk of carrying a fetus affected by homozygous alpha(0)-thalassemia were studied from 1995 to 2006 using serial ultrasonography at 12-15 weeks, 16-20 weeks and 30 weeks' gestation. We measured CTR and PT from 1995, and MCA-PSV as well from 1997. An invasive prenatal test was offered if cardiomegaly with or without placentomegaly was detected but the MCA-PSV results were used only retrospectively for analysis. RESULTS Of a total of 777 at-risk fetuses studied, 138 (17.8%) were affected by homozygous alpha(0)-thalassemia. At 12-15 weeks' gestation, 598 ultrasound examinations were performed. CTR was better than both PT and MCA-PSV in the prediction of affected pregnancies. The highest sensitivity (98.3%) was achieved by the combination of CTR and/or MCA-PSV at a false-positive rate of 15.8%. At 16-20 weeks' gestation, 410 ultrasound examinations were performed, 121 of which were at the patient's first visit and 289 of which were at a follow-up visit. Both CTR and MCA-PSV predicted the affected pregnancies equally well. The sensitivity of CTR was 100.0%, but the false-positive rate was 5.2%. In contrast, the false-positive rate of MCA-PSV alone was 1.4% and that of the combination of CTR and MCA-PSV was 0%, although their sensitivities were less than 65%. CONCLUSIONS The data suggest that adding MCA-PSV to CTR in the prediction of homozygous alpha(0)-thalassemia can increase the sensitivity at 12-15 weeks and decrease the false-positive rate at 16-20 weeks' gestation.
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Affiliation(s)
- K Y Leung
- Department of Obstetrics & Gynaecology, The University of Hong Kong, Queen Mary Hospital, Hong Kong, Republic of China.
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Quraishi J, Greiman A, Tang M, Shen J, Boushey H, Avila P, Favoreto S. Viperin Antiviral Response in Upper Airways is Similar in Asthmatic and Healthy Subjects. J Allergy Clin Immunol 2010. [DOI: 10.1016/j.jaci.2009.12.592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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173
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Tang M, Favoreto S, Greiman A, Shen J, Koterba A, Quraishi J, Avila P. Fractalkine May Enhance Antiviral Th1 Response via Dendritic Cells. J Allergy Clin Immunol 2010. [DOI: 10.1016/j.jaci.2009.12.590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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174
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Zhou H, Liu X, Liu L, Yang Z, Zhang S, Tang M, Tang Y, Dong Q, Hu R. Oxidative Stress and Apoptosis of Human Brain Microvascular Endothelial Cells Induced by Free Fatty Acids. J Int Med Res 2009; 37:1897-903. [PMID: 20146889 DOI: 10.1177/147323000903700627] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Damage to endothelial cells is a key event in the pathogenesis of atherosclerosis and vascular disease. This study aimed to determine whether free fatty acids (FFAs) induced oxidative stress and apoptosis in human brain microvascular endothelial cells (HBMVECs) in vitro and, if so, which signalling pathway mediated these effects. After culture in different concentrations of FFAs for 24-72 h, cell viability/proliferation was determined using a cell counting kit, apoptosis was detected by measuring caspase-3 activity and by using annexin V-conjugated fluorescein isothiocyanate/propidium iodide staining, and oxidative stress was evaluated by measuring the levels of reactive oxygen species (ROS) and mitochondrial membrane potential (MMP). The HBMVECs exposed to FFAs showed significantly decreased cell proliferation, increased apoptosis and ROS levels, and decreased MMP. In conclusion, the results showed that high levels of FFAs induced oxidative stress, which damaged HBMVECs and resulted in apoptosis.
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Affiliation(s)
- H Zhou
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China
- Department of Neurology, Changshu Hospital, Yangzhou University, Changshu, China
| | - X Liu
- Department of Neurology, Shanghai 10th Hospital, Tongji University, Shanghai, China
| | - L Liu
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China
| | - Z Yang
- Department of Endocrinology, Huashan Hospital, Fudan University, Shanghai, China
| | - S Zhang
- Department of Endocrinology, Huashan Hospital, Fudan University, Shanghai, China
| | - M Tang
- Department of Neurology, 1st Hospital, Zhejiang University, Hangzhou, China
| | - Y Tang
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China
| | - Q Dong
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China
| | - R Hu
- Department of Endocrinology, Huashan Hospital, Fudan University, Shanghai, China
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175
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Huang Y, Dai Y, Yang J, Chen T, Yin Y, Tang M, Hu C, Zhang L. Microarray analysis of microRNA expression in renal clear cell carcinoma. Eur J Surg Oncol 2009; 35:1119-23. [DOI: 10.1016/j.ejso.2009.04.010] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2008] [Revised: 04/11/2009] [Accepted: 04/15/2009] [Indexed: 12/14/2022] Open
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176
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Guo JK, Lin YB, Zhao ML, Sun R, Wang TT, Tang M, Wei GH. Streptomyces plumbiresistens sp. nov., a lead-resistant actinomycete isolated from lead-polluted soil in north-west China. Int J Syst Evol Microbiol 2009; 59:1326-30. [DOI: 10.1099/ijs.0.004713-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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177
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Broekhuizen L, Meuwese M, Mooij H, Lemkes B, Gouverneur M, Tang M, Verberne H, Nieuwdorp M, Vink H, Stroes E. Abstract: P215 EFFECT OF SULODEXIDE ON ENDOTHELIAL GLYCOCALYX AND VASCULAR PERMEABILITY IN PATIENTS WITH TYPE II DIABETES MELLITUS. ATHEROSCLEROSIS SUPP 2009. [DOI: 10.1016/s1567-5688(09)70522-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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178
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Li HY, Zhang R, Sun GY, Tang M, Gleason ML. First Report of Sooty Blotch and Flyspeck Caused by Species of Dissoconium, Mycosphaerella, and Peltaster on Hawthorn Fruit in China. Plant Dis 2009; 93:670. [PMID: 30764423 DOI: 10.1094/pdis-93-6-0670a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Sooty blotch and flyspeck (SBFS), a disease complex comprised of as many as 30 putative species of fungi, occurs on the cuticle of pome fruits in moist production regions worldwide, inciting cosmetic damage that causes significant economic losses (1). Chinese hawthorn (Crataegus pinnatifida Bge.) is an economically important tree species in China. Its fruit are sold fresh or dried and are used as a culinary spice as well as an ingredient in Chinese traditional medicine. In October of 2007, Chinese hawthorn fruit exhibiting SBFS signs were sampled from supermarkets in Yangling, Shaanxi Province and Luoyang, Henan Province, China. Thalli directly from the hawthorn fruit were transferred onto potato dextrose agar (PDA) slants under a dissecting microscope and cultured at 22 ± 1°C in darkness. DNA was extracted from pure isolates and the internal transcribed spacer (ITS) region of the nuclear ribosomal DNA (nrDNA) was amplified and sequenced using primers ITS-1F and ITS4 (3). Phylogenetic analysis of the ITS sequences revealed that the 35 isolates generated in this study included five species in three genera: Dissoconium sp. (18 isolates), Mycosphaerella sp. (5 isolates), and Peltaster sp. 1 (4 isolates), Peltaster sp. 2 (4 isolates), and Peltaster sp. 3 (4 isolates). To fulfill Koch's postulates and verify that these fungi could also infest apple fruit, two representative isolates of each putative species were inoculated onto mature intact hawthorn and apple (cv. Fuji) fruit that had been surface disinfested with 75% ethanol and allowed to dry. Inoculum was prepared by comminuting 1-month-old cultures growing on PDA into a suspension of mycelial fragments and conidia (105 to ~106 CFU/ml) in a blender with sterile deionized water (SDW). Each isolate was inoculated on three hawthorn and three apple fruit by using cotton swabs. As controls, two surface-disinfested hawthorn and apple fruit were swabbed with SDW. After the inoculated hawthorn and apple fruit had been incubated in a moist chamber at 22 ± 1°C for 1 month, all inoculated hawthorn and apple fruit exhibited SBFS signs similar to those of the original colonies on hawthorn fruit, but the controls did not. Reservoir hosts have been inferred to play an important role in SBFS by providing the fungi with overwintering habitat and inoculum for infestations on apple. Many reservoir hosts have been reported in the United States and Japan (2). To our knowledge, this is the first report of fungi in the SBFS complex on hawthorn fruit and the first confirmation that fungi growing on hawthorn fruit can produce SBFS signs on apple fruit. These results identify hawthorn as a potential inoculum source for SBFS in apple orchards. References: (1) J. C. Batzer et al. Mycologia 97:1283, 2005. (2) K. Hemnani et al. Phytopathology 98(suppl):S66, 2008. (3) T. J. White et al. PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, San Diego, 1990.
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Affiliation(s)
- H Y Li
- College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - R Zhang
- College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - G Y Sun
- College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - M Tang
- College of Forestry, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - M L Gleason
- Department of Plant Pathology, Iowa State University, Ames 50011
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Tang M, Kriatselis C, Nedios S, Roser M, Fleck E, Gerds-Li JH, De Buck S, Ector J, La Gerche A, Maes F, Hein Heidbuchel H, Doshi SK, Neuzil P, Reddy VY, Lickfett L, Becker P, Noe P, Linhart M, Lewalter T, Schrickel JW, Nickenig G, Mittmann-Braun EL, Wieczorek M, Hoeltgen R, Braun P, Sinha AM, Mahnkopf C, Ritscher G, Burgon N, Schmidt M, Marschang H, Marrousche NF, Brachmann J. Abstracts: New techniques for atrial fibrillation ablation. Europace 2009. [DOI: 10.1093/europace/euq201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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180
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Xue Y, Tang M, Hieda Y, Fujihara J, Takayama K, Takatsuka H, Takeshita H. High-Performance Liquid Chromatographic Determination of Chlorhexidine in Whole Blood by Solid-Phase Extraction and Kinetics Following an Intravenous Infusion in Rats. J Anal Toxicol 2009; 33:85-91. [DOI: 10.1093/jat/33.2.85] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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181
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Tang M, Favoreto Jr. S, Fiuk J, Shen J, Quraishi J, Avila P. Airway Epithelial Cells From Asthmatic Subjects Produce More Fractalkine (CX3CL1) Than Those Of Healthy Subjects Upon Rhinovirus Infection. J Allergy Clin Immunol 2009. [DOI: 10.1016/j.jaci.2008.12.249] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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182
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Kriatselis C, Tang M, Roser M, Fleck E, Gerds-Li H. A new approach for contrast-enhanced X-ray imaging of the left atrium and pulmonary veins for atrial fibrillation ablation: rotational angiography during adenosine-induced asystole. Europace 2008; 11:35-41. [DOI: 10.1093/europace/eun311] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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183
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Hankey GJ, Algra A, Chen C, Wong MC, Cheung R, Wong L, Divjak I, Ferro J, de Freitas G, Gommans J, Groppa S, Hill M, Spence D, Lees K, Lisheng L, Navarro J, Ranawaka U, Ricci S, Schmidt R, Slivka A, Tan K, Tsiskaridze A, Uddin W, Vanhooren G, Xavier D, Armitage J, Hobbs M, Le M, Sudlow C, Wheatley K, Yi Q, Bulder M, Eikelboom JW, Hankey GJ, Ho WK, Jamrozik K, Klijn K, Koedam E, Langton P, Nijboer E, Tuch P, Pizzi J, Tang M, Antenucci M, Chew Y, Chinnery D, Cockayne C, Loh K, McMullin L, Smith F, Schmidt R, Chen C, Wong MC, de Freitas G, Hankey GJ, Loh K, Song S. VITATOPS, the VITAmins TO prevent stroke trial: rationale and design of a randomised trial of B-vitamin therapy in patients with recent transient ischaemic attack or stroke (NCT00097669) (ISRCTN74743444). Int J Stroke 2008; 2:144-50. [PMID: 18705976 DOI: 10.1111/j.1747-4949.2007.00111.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Epidemiological studies suggest that raised plasma concentrations of total homocysteine (tHcy) may be a common, causal and treatable risk factor for atherothromboembolic ischaemic stroke, dementia and depression. Although tHcy can be lowered effectively with small doses of folic acid, vitamin B(12) and vitamin B(6), it is not known whether lowering tHcy, by means of B vitamin therapy, can prevent stroke and other major atherothromboembolic vascular events. AIM To determine whether the addition of B-vitamin supplements (folic acid 2 mg, B(6) 25 mg, B(12) 500 microg) to best medical and surgical management will reduce the combined incidence of stroke, myocardial infarction (MI) and vascular death in patients with recent stroke or transient ischaemic attack (TIA) of the brain or eye. DESIGN A prospective, international, multicentre, randomised, double blind, placebo-controlled clinical trial. SETTING One hundred and four medical centres in 20 countries on five continents. SUBJECTS Eight thousand (6600 recruited as of 5 January, 2006) patients with recent (<7 months) stroke (ischaemic or haemorrhagic) or TIA (brain or eye). RANDOMISATION Randomisation and data collection are performed by means of a central telephone service or secure internet site. INTERVENTION One tablet daily of either placebo or B vitamins (folic acid 2 mg, B(6) 25 mg, B(12) 500 mug). PRIMARY OUTCOME The composite of stroke, MI or death from any vascular cause, whichever occurs first. Outcome and serious adverse events are adjudicated blinded to treatment allocation. SECONDARY OUTCOMES TIA, unstable angina, revascularisation procedures, dementia, depression. STATISTICAL POWER: With 8000 patients followed up for a median of 2 years and an annual incidence of the primary outcome of 8% among patients assigned placebo, the study will have at least 80% power to detect a relative reduction of 15% in the incidence of the primary outcome among patients assigned B vitamins (to 6.8%/year), applying a two-tailed level of significance of 5%. CONCLUSION VITATOPS aims to recruit and follow-up 8000 patients between 1998 and 2008, and provide a reliable estimate of the safety and effectiveness of folic acid, vitamin B(12), and vitamin B(6) supplementation in reducing recurrent serious vascular events among a wide range of patients with TIA and stroke throughout the world.
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184
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Tan EK, Tan LC, Lim HQ, Li R, Tang M, Yih Y, Pavanni R, Prakash KM, Fook-Chong S, Zhao Y. LRRK2 R1628P increases risk of Parkinson’s disease: replication evidence. Hum Genet 2008; 124:287-8. [DOI: 10.1007/s00439-008-0544-2] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2008] [Accepted: 08/09/2008] [Indexed: 10/21/2022]
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185
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Blanco R, Tang M, Angulo B, Sanchez-Céspedes M. Gene alteration profile and correlation to sensitivity to small molecule inhibitors in lung cancer cell lines. EJC Suppl 2008. [DOI: 10.1016/s1359-6349(08)71293-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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186
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Tang M, Davidoff AJ, Mullins CD, McNally D, Seal B, Edelman MJ. Chemotherapy (C) and survival among 21,441 elderly (E) patients (pts) with advanced (adv) NSCLC: Analysis of SEER-Medicare claim data 1997-2002. J Clin Oncol 2008. [DOI: 10.1200/jco.2008.26.15_suppl.8090] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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187
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Edelman MJ, Tang M, Gardner JF, Mullins CD, Seal B, Davidoff AJ. Therapy (Tx) of locally advanced (LA) NSCLC in the elderly: Analysis of 6,325 patients from Surveillance, Epidemiology and End Results (SEER)-Medicare. J Clin Oncol 2008. [DOI: 10.1200/jco.2008.26.15_suppl.7549] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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188
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Dai Y, Huang YS, Tang M, Lv TY, Hu CX, Tan YH, Xu ZM, Yin YB. Microarray analysis of microRNA expression in peripheral blood cells of systemic lupus erythematosus patients. Lupus 2008; 16:939-46. [PMID: 18042587 DOI: 10.1177/0961203307084158] [Citation(s) in RCA: 261] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
MicroRNAs (miRNAs) are noncoding RNA molecules of 21-24 nt that regulate the expression of target genes in a post-transcriptional manner. Evidence indicates that miRNAs play essential roles in embryogenesis, cell differentiation and pathogenesis of human diseases. This study describes a comparison between the miRNA profile of the systemic lupus erythematosus (SLE) patients and the controls to develop further understanding of the pathogenesis of SLE. Peripheral blood mononuclear cells were isolated from blood samples of 23 SLE patients, 10 idiopathic thrombocytopenic purpura patients and 10 healthy controls. The miRNA microarray chip analysis identified 16 miRNAs differentially expressed in SLE. The chip results were confirmed by northern blot analysis. This work indicates that miRNAs are potential diagnosis biomarkers and probable factors involved in the pathogenesis of SLE.
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Affiliation(s)
- Y Dai
- The Second Clinical Medical College, Jinan University, Shenzhen People's Hospital, Guangdong Province, China
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189
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Angulo B, Suarez-Gauthier A, Lopez-Rios F, Medina PP, Conde E, Tang M, Soler G, Lopez-Encuentra A, Cigudosa JC, Sanchez-Cespedes M. Expression signatures in lung cancer reveal a profile for EGFR-mutant tumours and identify selective PIK3CA overexpression by gene amplification. J Pathol 2008; 214:347-56. [PMID: 17992665 DOI: 10.1002/path.2267] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The development of targeted therapies creates a need to discriminate tumours accurately by their histological and genetic characteristics. Here, we aim to identify gene expression profiles and single markers that recapitulate the pathological and genetic background of non-small cell lung cancer (NSCLC). We performed cDNA microarray analysis on a series of 69 NSCLCs, with known mutation status for important genes, and six normal lung tissues. Unsupervised cluster analysis segregated normal lungs from lung tumours and lung tumours according to their histopathology and the presence of EGFR mutations. Several transcripts were highly overexpressed (by approximately 20 times) in squamous cell carcinomas (SCCs) relative to adenocarcinomas (ACs) and confirmed by immunohistochemistry in an independent cohort of 75 lung tumours. Expression of 13 genes constituted the most prominent hallmarks of EGFR-mutant tumours, including increased levels of proline dehydrogenase (PRODH) and down-regulation of X-box binding protein 1 (XBP1). No genes were differentially expressed, with a fold change >or= 4 or <or=0.25 and a significance level of 5% false-discovery rate, in tumours carrying mutations of TP53 or KRAS. In addition, we organized gene expression data by the position of each gene in the chromosome and observed a cluster of highly expressed genes in chromosome 3q, including PIK3CA, that was characteristic of SCCs. FISH analysis demonstrated a strong statistically significant association between increased levels of PIK3CA expression in these tumours and gene amplification (p < 0.0001; t-test). In conclusion, histopathological phenotypes and, likely, the presence of EGFR mutations confer lung tumours with a marked pattern of gene expression. Moreover, our cDNA microarray analysis identified increased PIK3CA expression due to gene amplification in lung squamous cell carcinomas: this may represent a marker of sensitivity to therapy with PI3K inhibitors.
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Affiliation(s)
- B Angulo
- Lung Cancer Group, Spanish National Cancer Centre (CNIO), 28029 Madrid, Spain
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190
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Phogat S, Svehla K, Tang M, Spadaccini A, Muller J, Mascola J, Berkower I, Wyatt R. Analysis of the human immunodeficiency virus type 1 gp41 membrane proximal external region arrayed on hepatitis B surface antigen particles. Virology 2007; 373:72-84. [PMID: 18155743 DOI: 10.1016/j.virol.2007.11.005] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2007] [Revised: 09/26/2007] [Accepted: 11/06/2007] [Indexed: 10/22/2022]
Abstract
Vaccine immunogens derived from the envelope glycoproteins of the human immunodeficiency virus type 1 (HIV-1) that elicit broad neutralizing antibodies remain an elusive goal. The highly conserved 30 amino-acid membrane proximal external region (MPER) of HIV gp41 contains the hydrophobic epitopes for two rare HIV-1 broad cross-reactive neutralizing antibodies, 2F5 and 4E10. Both these antibodies possess relatively hydrophobic HCDR3 loops and demonstrate enhanced binding to their epitopes in the context of the native gp160 precursor envelope glycoprotein by the intimate juxtaposition of a lipid membrane. The hepatitis B surface antigen (HBsAg) S1 protein forms nanoparticles that can be utilized both as an immunogenic array of the MPER and to provide the lipid environment needed for enhanced 2F5 and 4E10 binding. We show that recombinant HBsAg particles with MPER (HBsAg-MPER) appended at the C-terminus of the S1 protein are recognized by 2F5 and 4E10 with high affinity compared to positioning the MPER at the N-terminus or the extracellular loop (ECL) of S1. Addition of C-terminal hydrophobic residues derived from the HIV-1 Env transmembrane region further enhances recognition of the MPER by both 2F5 and 4E10. Delipidation of the HBsAg-MPER particles decreases 2F5 and 4E10 binding and subsequent reconstitution with synthetic lipids restores optimal binding. Inoculation of the particles into small animals raised cross-reactive antibodies that recognize both the MPER and HIV-1 gp160 envelope glycoproteins expressed on the cell surface; however, no neutralizing activity could be detected. Prime:Boost immunization of the HBsAg-MPER particles in sequence with HIV envelope glycoprotein proteoliposomes (Env-PLs) did not raise neutralizing antibodies that could be mapped to the MPER region. However, the Env-PLs did raise anti-Env antibodies that had the ability to neutralize selected HIV-1 isolates. The first generation HBsAg-MPER particles represent a unique means to present HIV-1 envelope glycoprotein neutralizing determinants to the immune system.
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Affiliation(s)
- S Phogat
- Structural Virology Section, Vaccine Research Center, NIAID, NIH, Bethesda, MD 20892-3005, USA
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191
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Abstract
Spatial and temporal dynamics of bark beetles in single tree trunks of Pinus armandi were studied in Qinling Mountains, Shaanxi Province, China. Ten species of engraver bark beetles attacked from healthy to withered Chinese white pines, but seven species were commonly detected every year in Qinling forest ecosystem. Dendroctonus armandi and Hylurgops longipilis were common species at the lower of trunks, and Ips acuminatus, Polygraphus sinensis, and Pityogenes japonicus primary distributed in the middle of trunks, whereas population densities of Cryphalus lipingensis and C. chinlingensis centralized at the upper trunks and branches of Chinese white pines. On the time series, D. armandi, as a dominant species in Chinese white pines of Qinling forest ecosystem, mainly attacked healthy and weakened trees and cooperated with blue stain fungus that resulted in the declining abruptly resistance and triggered the secondary bark beetles to attack the infected or withered host trees. Attacking and colonizing phenology of bark beetles in Qinling forest ecosystem are caused by complex interactions among spatial and trophic competition and cooperation and exhibit particular spatial and temporal patterns. Our results support the view that competition and cooperation within bark beetles are a critical factor to influence bark beetles spatial and temporal distribution, and stability of bark beetles' ecosystem, D. armandi, I. acuminatus, P. japonicus, P. sinensis, C. lipingensis, C. chinlingensis, and H. longipilis in Chinese white pine of Qinling forest ecosystem.
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Affiliation(s)
- H Chen
- College of Forestry, Northwest Agriculture and Forestry University, Yangling, Shaanxi 712100, China.
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192
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Dai Y, Huang YS, Tang M, Lv XP, Li TY, Yin YB. Distribution and clinical significance of human papillomavirus subtypes in Shenzhen city, People's Republic of China. Int J Gynecol Cancer 2007; 18:295-9. [PMID: 17624987 DOI: 10.1111/j.1525-1438.2007.01024.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
This study investigated the subtype distribution of the human papillomavirus (HPV) in the patients with condyloma accuminatum (CA) in Shenzhen city, China, and assessed the relationship between different HPV subtypes and cervical neoplasia. Type-specific prevalence and extent of multiple infections were assessed in the genital tract. CA samples collected from the 352 patients in the departments of dermatology and gynecology from the People's Hospital in Shenzhen during 2004-2006, using MY09/11 PCR and reverse dot blot hybridization for genotyping of 9-20 kinds of HPV subtypes. HPV status was studied in relation to the pathologic findings. HPV type diversity was wide. The low-risk HPV subtype 11 and 6 were the main subtypes, and multiple HPV infection rate was about 37% in HPV-positive samples. High-risk HPV (HR-HPV) types (16, 18, 58, 52, and 33) were the main subtypes in the CA of cervix, especially in the advanced stage cervical intraepithelial neoplasia (cervical intraepithelial neoplasia II(+) or above), multiple HR-HPV infection was found in 87% of HPV-positive samples. We conclude that HPV type 6 and 11 were the main subtypes in patients with CA in Shenzhen region, while HPV type 16 and 18 may be one of the main reasons for malignant changes of cervix, but this study cannot prove the association between multiple HPV infection and severity of cervix lesions.
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Affiliation(s)
- Y Dai
- The Second Clinical Medical College, Jinan University, Shenzhen People's Hospital, Guangdong Province, China.
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193
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Cho YM, Takahashi S, Asamoto M, Suzuki S, Tang M, Shirai T. Suppressive effects of antiandrogens, finasteride and flutamide on development of prostatic lesions in a transgenic rat model. Prostate Cancer Prostatic Dis 2007; 10:378-83. [PMID: 17457304 DOI: 10.1038/sj.pcan.4500971] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Transgenic (TG) rats bearing a probasin promoter/simian virus 40 T antigen (SV40 Tag) construct were treated with antiandrogens to examine their ability to suppress prostate carcinogenesis. Finasteride and flutamide were administered to 10-week-old TG rats five times a week for 2, 5 and 7 weeks. Antiandrogen-treated prostates exhibited atrophic glandular structures with almost no expression of SV40 Tag and only weak signals for androgen receptors. Furthermore, quantitative data for ventral prostate adenocarcinomas showed significant decrease with antiandrogen treatment. Both finasteride and flutamide had the ability to suppress SV40 Tag-driven carcinogenesis through their different antiandrogenic mechanisms, suggesting that this TG model is suitable for exploring the potential of agents to inhibit prostate cancer development.
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Affiliation(s)
- Y-M Cho
- Department of Experimental Pathology and Tumor Biology, Nagoya City University Graduate School of Medical Sciences, Mizuho-cho, Mizuho-ku, Nagoya, Japan
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194
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Tang M, Chang CQ, Fung PCW, Chau KT, Chan FHY. An Improved Method for Discriminating ECG Signals using Typical Nonlinear Dynamic Parameters and Recurrence Quantification Analysis in Cardiac Disease Therapy. Conf Proc IEEE Eng Med Biol Soc 2007; 2005:2459-62. [PMID: 17282735 DOI: 10.1109/iembs.2005.1616966] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The discrimination of ECG signals using nonlinear dynamic parameters is of crucial importance in the cardiac disease therapy and chaos control for arrhythmia defibrillation in the cardiac system. However, the discrimination results of previous studies using features such as maximal Lyapunov exponent (λ<inf>max</inf>) and correlation dimension (D<inf>2</inf>) alone are somewhat limited in recognition rate. In this paper, improved methods for computing λ<inf>max</inf>and D<inf>2</inf>are purposed. Another parameter from recurrence quantification analysis is incorporated to the new multi-feature Bayesian classifier with λ<inf>max</inf>and D<inf>2</inf>so as to improve the discrimination power. Experimental results have verified the prediction using Fisher discriminant that the maximal vertical line length (V<inf>max</inf>) from recurrence quantification analysis is the best to distinguish different ECG classes. Experimental results using the MIT-BIH Arrhythmia Database show improved and excellent overall accuracy (96.3%), average sensitivity (96.3%) and average specificity (98.15%) for discriminating sinus, premature ventricular contraction and ventricular flutter signals.
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Affiliation(s)
- M Tang
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, PRC.
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195
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Morris S, Tang M, Geddes C. Bases anatómicas vasculares de los colgajos perforantes cutáneos. Cir Plást Iberlatinamer 2006. [DOI: 10.4321/s0376-78922006000400002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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196
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Carretero J, Medina PP, Blanco R, Smit L, Tang M, Roncador G, Maestre L, Conde E, Lopez-Rios F, Clevers HC, Sanchez-Cespedes M. Dysfunctional AMPK activity, signalling through mTOR and survival in response to energetic stress in LKB1-deficient lung cancer. Oncogene 2006; 26:1616-25. [PMID: 16953221 DOI: 10.1038/sj.onc.1209951] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
LKB1, mutated in Peutz-Jeghers and in sporadic lung tumours, phosphorylates a group of protein kinases named AMP-activated protein kinase (AMPK)-related kinases. Among them is included the AMPK, a sensor of cellular energy status. To investigate the relevance of LKB1 in lung carcinogenesis, we study several lung cancer cells with and without LKB1-inactivating mutations. We report that LKB1-mutant cells are deficient for AMPK activity and refractory to mTOR inhibition upon glucose depletion but not growth-factor deprivation. The requirement for wild-type LKB1 to properly activate AMPK is further demonstrated in genetically modified cancer cells. In addition, LKB1-deficient lung primary tumours had diminished AMPK activity, assessed by complete absence or low level of phosphorylation of its critical substrate, acetyl-CoA carboxylase. We also demonstrate that LKB1 wild-type cells are more resistant to cell death upon glucose withdrawal than their mutant counterparts. Finally, modulation of AMPK activity did not affect PI3K/AKT signalling, an advantage for the potential use of AMPK as a target for cancer therapy in LKB1 wild-type tumours. Thus, sustained abrogation of cell energetic checkpoint control, through alterations at key genes, appear to be an obligatory step in the development of some lung tumours.
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Affiliation(s)
- J Carretero
- Lung Cancer Group, Spanish National Cancer Centre (CNIO), Madrid, Spain
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197
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Reinisch W, Hommes DW, Van Assche G, Colombel JF, Gendre JP, Oldenburg B, Teml A, Geboes K, Ding H, Zhang L, Tang M, Cheng M, van Deventer SJH, Rutgeerts P, Pearce T. A dose escalating, placebo controlled, double blind, single dose and multidose, safety and tolerability study of fontolizumab, a humanised anti-interferon gamma antibody, in patients with moderate to severe Crohn's disease. Gut 2006; 55:1138-44. [PMID: 16492717 PMCID: PMC1856289 DOI: 10.1136/gut.2005.079434] [Citation(s) in RCA: 134] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
INTRODUCTION This study was designed to evaluate the safety of fontolizumab, a humanised anti-interferon gamma antibody, in patients with moderate to severe Crohn's disease (CD). PATIENTS AND METHODS Forty five patients with a CD activity index (CDAI) of 250-450 were randomised in a double blind, placebo controlled, dose escalating fashion to receive single doses of fontolizumab (0.1, 1.0, and 4.0 mg/kg) or placebo. By day 29, patients with clinical response were re-randomised to receive three additional doses of one half their initial fontolizumab dose or placebo at four weekly intervals. Primary objectives were safety and tolerability. Secondary outcomes included assessments of immunogenicity, clinical activity, and potential pharmacodynamic surrogates. RESULTS Treatment was generally well tolerated. There were slightly more reports of chills, flu-like syndrome, asthenia, nausea, and vomiting in the 1.0 mg and 4.0 mg/kg fontolizumab cohorts. Two serious adverse events rated as worsening of CD occurred under fontolizumab. Antibodies to fontolizumab were confirmed in one patient. No differences in clinical activity parameters were noted between any of the active treatment groups and placebo, with the placebo group having a particularly favourable outcome (60% response and 40% remission). By day 29, a more enhanced decrease in median Crohn's disease endoscopic index of severity (p = 0.02) and serum C reactive protein (p<0.001) was observed in the 4.0 mg/kg (n = 14) fontolizumab cohort compared with placebo (n = 10). Pharmacodynamic effects were observed by immunohistochemistry. CONCLUSIONS Fontolizumab was well tolerated with minimal immunogenicity at doses of up to 4.0 mg/kg in patients with CD. A biological activity of fontolizumab is suggested.
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Affiliation(s)
- W Reinisch
- Universitaetsklinik Innere Medizin IV, Abteilung Gastroenterologie and Hepatologie, Vienna, Austria.
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198
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Mani R, Tang M, Wu X, Buffy JJ, Waring AJ, Sherman MA, Hong M. Membrane-Bound Dimer Structure of a β-Hairpin Antimicrobial Peptide from Rotational-Echo Double-Resonance Solid-State NMR. Biochemistry 2006; 45:8341-9. [PMID: 16819833 DOI: 10.1021/bi060305b] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The intermolecular packing of a beta-hairpin antimicrobial peptide, PG-1, in lipid bilayers is determined using solid-state NMR distance measurements. Previous spin counting experiments showed that PG-1 associates as dimers in POPC bilayers; however, the detailed dimer structure was unknown. We have now measured several intermolecular 13C-19F, 1H-13C, and 15N-13C distances in site-specifically labeled PG-1 to constrain the structure of the intermolecular interface. The distances are measured using the rotational-echo double-resonance (REDOR) technique under magic-angle spinning. The results indicate that two PG-1 molecules align in a parallel fashion with the C-terminal strand of the hairpin forming the dimer interface. Six hydrogen bonds stabilize this interface, and the Phe12 side chain adopts the g- conformation in the membrane as in solution. The parallel packing of the peptide in the lipid bilayer differs from the antiparallel dimer found in DPC micelles and may be stabilized by its strong amphipathic character, which should facilitate its insertion into the amphipathic lipid bilayer. This study demonstrates the utility of the REDOR NMR technique for the elucidation of the oligomeric structure of membrane proteins.
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Affiliation(s)
- R Mani
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, USA
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199
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Dong J, Peeters TL, De Smet B, Moechars D, Delporte C, Vanden Berghe P, Coulie B, Tang M, Depoortere I. Role of endogenous ghrelin in the hyperphagia of mice with streptozotocin-induced diabetes. Endocrinology 2006; 147:2634-42. [PMID: 16484325 DOI: 10.1210/en.2005-1335] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Ghrelin is an orexigenic peptide involved in the regulation of energy homeostasis. To investigate the role of ghrelin in the hyperphagia associated with uncontrolled streptozotocin-induced diabetes, food intake was followed in diabetic ghrelin knockout (ghrelin(-/-)) and control wild-type (ghrelin(+/+)) mice and diabetic Naval Medical Research Institute noninbred Swiss mice treated with either saline or the ghrelin receptor antagonist, D-Lys3-GH-releasing peptide-6 (D-Lys3-GHRP-6) for 5 d. In diabetic ghrelin(-/-) mice, hyperphagia was attenuated, and the maximal increase in food intake was 50% lower in mutant than in wild-type mice. The increased food intake observed during the light period (1000-1200 h) in ghrelin(+/+) mice was abolished in mutant mice. Diabetic ghrelin(-/-) mice lost 12.4% more body weight than ghrelin(+/+) mice. In diabetic ghrelin(+/+) mice, but not in ghrelin(-/-) mice, the number of neuropeptide Y (NPY)-immunoreactive neurons was significantly increased. Diabetic Naval Medical Research Institute noninbred Swiss mice were hyperphagic and had increased plasma ghrelin levels. Treatment with D-Lys3-GHRP-6 reduced daily food intake by 23% and reversed the increased food intake observed during the light period. The change in the number of NPY- (2.4-fold increase) and alpha-MSH (1.7-fold decrease)-immunoreactive hypothalamic neurons induced by diabetes was normalized by D-Lys3-GHRP-6 treatment. Our results suggest that enhanced NPY and reduced alpha-MSH expression are secondary to the release of ghrelin, which should be considered the underlying trigger of hyperphagia associated with uncontrolled diabetes.
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Affiliation(s)
- J Dong
- Center for Gastroenterological Research, Catholitic University of Leuven, 3000 Leuven, Belgium
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200
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Tang M, Tian X, Shum P, Fu S, Dong H, Gong Y. Four-wave mixing assisted self-stable 4x10 GHz actively mode-locked Erbium fiber ring laser. Opt Express 2006; 14:1726-1730. [PMID: 19503500 DOI: 10.1364/oe.14.001726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We proposed and developed a self-stable multiwavelength (4 cbannels) 10-GHz actively mode-locked Erbium-doped fiber ring laser with 0.8 nm wavelength spacing. A 1-km highly nonlinear fiber is incorporated in the laser cavity to eliminate the strong gain competitions in the homogeneously broadened EDF by multiple parametric four-wave mixing processes. The fiber nonlinearity is also helpful to provide phase locking and stabilize the output pulse. Stable laser pulses at 1556.55, 1557.36, 1558.17, and 1558.98 nm are successfully obtained simultaneously with supermode noise suppression ratio greater than 50 dB. The corresponding time-bandwidth products of four channels are 0.39 ~ 0.41.
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