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Yuan WX, Chen SR, Chen H, Pan HL. Stimulation of alpha(1)-adrenoceptors reduces glutamatergic synaptic input from primary afferents through GABA(A) receptors and T-type Ca(2+) channels. Neuroscience 2008; 158:1616-24. [PMID: 19068225 DOI: 10.1016/j.neuroscience.2008.11.022] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2008] [Revised: 11/07/2008] [Accepted: 11/11/2008] [Indexed: 11/20/2022]
Abstract
Activation of the descending noradrenergic system inhibits nociceptive transmission in the spinal cord. Although both alpha(1)- and alpha(2)-adrenoceptors in the spinal cord are involved in the modulation of nociceptive transmission, it is not clear how alpha(1)-adrenoceptors regulate excitatory and inhibitory synaptic transmission at the spinal level. In this study, inhibitory and excitatory postsynaptic currents (IPSCs and EPSCs, respectively) were recorded from lamina II neurons in rat spinal cord slices. The specific alpha(1)-adrenoceptor agonist phenylephrine significantly increased the frequency of GABAergic spontaneous IPSCs in a concentration dependent manner, and this effect was abolished by the alpha(1)-adrenoceptor antagonist 2-(2,6-dimethoxyphenoxy)ethylaminomethyl-1,4-benzodioxane (WB4101). Phenylephrine also significantly reduced the amplitude of monosynaptic and polysynaptic EPSCs evoked from primary afferents. The inhibitory effect of phenylephrine on evoked monosynaptic glutamatergic EPSCs was largely blocked by the GABA(A) receptor antagonist picrotoxin and, to a lesser extent, by the GABA(B) receptor antagonist CGP55845. Furthermore, blocking T-type Ca(2+) channels with amiloride or mibefradil diminished the inhibitory effect produced by phenylephrine or the GABA(A) receptor agonist muscimol on monosynaptic EPSCs evoked from primary afferents. Collectively, these findings suggest that activation of alpha(1)-adrenoceptors in the spinal cord increases synaptic GABA release, which attenuates glutamatergic input from primary afferents mainly through GABA(A) receptors and T-type Ca(2+) channels. This mechanism of presynaptic inhibition in the spinal cord may be involved in the regulation of nociception by the descending noradrenergic system.
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Zhang WX, Chen B, Jin Z, Yu Z, Wang X, Chen H, Mao A, Cai W. Influence of uridine diphosphate (UDP)-glucuronosyltransferases and ABCC2 genetic polymorphisms on the pharmacokinetics of mycophenolic acid and its metabolites in Chinese renal transplant recipients. Xenobiotica 2008; 38:1422-36. [DOI: 10.1080/00498250802488585] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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2253
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Zhang Q, Wang Y, Wei L, Jiang D, Wang JH, Rao HY, Zhu L, Chen H, Fei R, Cong X. Role of ISGF3 in modulating the anti-hepatitis B virus activity of interferon-alpha in vitro. J Gastroenterol Hepatol 2008; 23:1747-61. [PMID: 17559358 DOI: 10.1111/j.1440-1746.2007.04985.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND AND AIM Although interferon-alpha (IFN-alpha) is an effective treatment for hepatitis B virus (HBV) infection, its precise mechanism of action has not been identified. In this study, we investigated the role of signal transduction pathways in the activation of anti-HBV responses mediated by IFN-alpha. METHODS Using an oligo microarray, we found that four genes in the IFN-alpha signal pathway were markedly upregulated by IFN-alpha in human hepatoma cells regardless of whether they had been transfected with a plasmid containing the HBV genome: signal transducers and activators of transcription 1 (STAT1), interferon regulatory factor-9 (IRF-9, also called ISGF3gamma or P48), IFN-alpha-inducible protein 15 (IFI-15) and IFN-alpha-inducible protein 6-16 (IFI-6-16). We also investigated the role of IFN-stimulated gene factor3 (ISGF3) complex in IFN-alpha-mediated anti-HBV responses in human hepatoma cells by measuring the mRNA of the three genes within ISGF3 (STAT1, STAT2 and IRF-9) using semiquantitative reverse-transcription PCR (RT-PCR), and expression of the three proteins by western blot, and the mRNA and protein of dsRNA-dependent protein kinase (PKR). RESULTS STAT1, STAT2, IRF-9 and PKR mRNA as well as protein levels were upregulated by IFN-alpha treatment. When cells were pretreated with genistein, STAT1, STAT2 and IRF-9 mRNA levels remained unchanged after IFN-alpha stimulation, but PKR mRNA levels decreased, and the expression of the STAT1, P-STAT2, IRF-9 and PKR proteins decreased. Levels of HBV DNA decreased in the supernatants of cells treated with IFN-alpha, while ISGF3 levels increased. The quantity of HBV DNA remained unchanged by pretreating with genistein. CONCLUSIONS These observations suggested that the Janus tyrosine kinase-STAT (JAK-STAT) pathway may play a major role in mediating the effects of IFN-alpha against HBV, and that ISGF3 might be a key factor.
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Yu H, Wang X, Chen H, Wang M, Zhao M, Lan X, Lei C, Wang K, Lai X, Wang X. The polymorphism of a novel 30bp-deletion mutation at KAP9.2 locus in the cashmere goat. Small Rumin Res 2008. [DOI: 10.1016/j.smallrumres.2008.09.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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2255
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Zhao X, Wang YW, Chen H, Zhang Z, You XM, Luo K, Jin YJ. Efficacy of Low Dose Levobupivacaine (0.1%) for Axillary Plexus Block using Multiple Nerve Stimulation. Anaesth Intensive Care 2008; 36:850-4. [PMID: 19115656 DOI: 10.1177/0310057x0803600616] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The purpose of this study was to investigate if low doses of levobupivacaine (0.1%) produce complete sensory blockade in preoperative axillary brachial plexus block and to compare the effect of different doses of levobupivacaine on sensory and motor blockade. A total of 110 patients scheduled for elective forearm or hand surgery were randomly allocated to receive 36 ml or 72 ml of levobupivacaine 0.1% or 36 ml of levobupivacaine 0.25%. In each group, volumes were equally distributed in the four nerve territories. In all patients, the sensory and motor block was assessed at five, 10, 20 and 30 minutes after the placement of axillary block. Complete sensory block was obtained in 94.4% of patients receiving 36 ml of levobupivacaine 0.1%, 92.1% of those receiving 72 ml of levobupivacaine 0.1%, and 97.1% of those receiving 36 ml of levobupivacaine 0.25%. There was no significant difference either in the onset of the sensory and motor block or duration of the sensory and motor block. This study demonstrates that 36 ml of levobupivacaine 0.1% (36 mg) is as effective as higher doses and volumes in axillary brachial plexus blockade.
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2256
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Duan L, Bahl J, Smith G, Wang J, Vijaykrishna D, Zhang L, Zhang J, Li K, Fan X, Cheung C, Huang K, Poon L, Shortridge K, Webster R, Peiris J, Chen H, Guan Y. The development and genetic diversity of H5N1 influenza virus in China, 1996-2006. Virology 2008; 380:243-54. [PMID: 18774155 PMCID: PMC2651962 DOI: 10.1016/j.virol.2008.07.038] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2008] [Revised: 07/22/2008] [Accepted: 07/25/2008] [Indexed: 02/05/2023]
Abstract
Since it was first detected in 1996, the Goose/Guangdong/1/1996 (Gs/GD) H5N1 influenza virus and its reassortants have spread to over 60 countries, with over 20 distinct genetic reassortants previously recognized. However, systematic analysis of their interrelationship and the development of genetic diversity have not been explored. As each of those reassortants was first detected in China, here 318 full-length H5N1 virus genomes isolated from 1996 to 2006 in this region were phylogenetically analyzed. Our findings revealed two major group reassortment events in 2001 and 2002 that were responsible for the generation of the majority of the 44 distinct Gs/GD genotypes identified, excepting those 1997 variants. Genotype replacement and emergence occurred continually, with 34 transient genotypes detected while only 10 variants were persistent. Two major replacements of predominant genotypes were also observed: genotype B replaced by Z in 2002 and then genotype Z replaced by the now predominant genotype V in 2005.
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Zhang C, Chen H, Zhang L, Zhao M, Guo Y, Zhang C, Lan X, Hu S. Association of polymorphisms of the <i>GHRHR</i> gene with growth traits in cattle (Brief report). Arch Anim Breed 2008. [DOI: 10.5194/aab-51-300-2008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Abstract. The hypothalamic hormone, growth hormone-releasing hormone (GHRH), is the principal stimulator of pituitary growth hormone (GH) synthesis and secretion. Its pituitary receptor is well characterized as a member of the superfamily of G protein-coupled receptors (MAYO et al., 1992). GHRH and its receptor provide important functions in the regulation of the GH axis and in the development and proliferation of pituitary somatotropes (LIN-SU et al., 2002). By now, polymorphisms of bovine GHRHR were not reported. In the present experiment the 5' flanking region, the coding region and partially introns of GHRHR were screened to detect the SNPs in the predominant cattle breeds of China.
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Lan X, Pan C, Hu S, Chen H. PCR-SSCP and <i>Hin6</i>I PCR-RFLP detecting novel anonymous SNPs within ovine <i>PROP1</i> gene (Brief report). Arch Anim Breed 2008. [DOI: 10.5194/aab-51-622-2008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Abstract. PROP1 plays a direct or indirect key role in the ontogenesis of pituitary gonadotropes, as well as somatotropes, lactotropes and caudomedial thyrotropes (WU et al., 1998). Mutations of PROP1 are responsible for deficiencies of POU1F1, GH, prolactin (PRL) and thyroid stimulating hormone (TSH) in Snell and Jackson dwarf mice and in man, as well as deficiencies of LH and FSH, suggesting that the PROP1 gene is a potential candidate gene associating with production traits in animal breeding and genetics. To date, no polymorphism of PROP1 gene has been reported in ruminant animals except bovine (PAN et al., 2007). So, the objective of this study is to investigate the polymorphism of all coding regions within ovine PROP1 gene by PCR-SSCP, DNA sequencing and PCR-RFLP methods, which will possibly contribute to conducting association analysis and evaluating them as genetic markers in animal breeding and genetics.
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2259
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Chen H, Tang J, Liu F. Simulation model for moving food packages in microwave heating processes using conformal FDTD method. J FOOD ENG 2008. [DOI: 10.1016/j.jfoodeng.2008.02.020] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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MacPhee AG, Akli KU, Beg FN, Chen CD, Chen H, Clarke R, Hey DS, Freeman RR, Kemp AJ, Key MH, King JA, Le Pape S, Link A, Ma TY, Nakamura H, Offermann DT, Ovchinnikov VM, Patel PK, Phillips TW, Stephens RB, Town R, Tsui YY, Wei MS, Van Woerkom LD, Mackinnon AJ. Diagnostics for fast ignition science (invited). THE REVIEW OF SCIENTIFIC INSTRUMENTS 2008; 79:10F302. [PMID: 19044615 DOI: 10.1063/1.2978199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The ignition concept for electron fast ignition inertial confinement fusion requires sufficient energy be transferred from an approximately 20 ps laser pulse to the compressed fuel via approximately MeV electrons. We have assembled a suite of diagnostics to characterize such transfer, simultaneously fielding absolutely calibrated extreme ultraviolet multilayer imagers at 68 and 256 eV; spherically bent crystal imagers at 4.5 and 8 keV; multi-keV crystal spectrometers; MeV x-ray bremmstrahlung, electron and proton spectrometers (along the same line of sight), and a picosecond optical probe interferometer. These diagnostics allow careful measurement of energy transport and deposition during and following the laser-plasma interactions at extremely high intensities in both planar and conical targets. Together with accurate on-shot laser focal spot and prepulse characterization, these measurements are yielding new insights into energy coupling and are providing critical data for validating numerical particle-in-cell (PIC) and hybrid PIC simulation codes in an area crucial for fast ignition and other applications. Novel aspects of these diagnostics and how they are combined to extract quantitative data on ultrahigh intensity laser-plasma interactions are discussed.
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2261
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Chen CD, King JA, Key MH, Akli KU, Beg FN, Chen H, Freeman RR, Link A, Mackinnon AJ, MacPhee AG, Patel PK, Porkolab M, Stephens RB, Van Woerkom LD. A Bremsstrahlung spectrometer using k-edge and differential filters with image plate dosimeters. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2008; 79:10E305. [PMID: 19044467 DOI: 10.1063/1.2964231] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A Bremsstrahlung spectrometer using k-edge and differential filtering has been used with image plate dosimeters to measure the x-ray fluence from short-pulse laser/target interactions. An electron spectrometer in front of the Bremsstrahlung spectrometer deflects electrons from the x-ray line of sight and simultaneously measures the electron spectrum. The response functions were modeled with the Monte Carlo code INTEGRATED TIGER SERIES 3.0 and the dosimeters calibrated with radioactive sources. An electron distribution with a slope temperature of 1.3 MeV is inferred from the Bremsstrahlung spectra.
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Chen H, Shoumura S, Emura S, Bunai Y. Regional variations of vertebral trabecular bone microstructure with age and gender. Osteoporos Int 2008; 19:1473-83. [PMID: 18330606 DOI: 10.1007/s00198-008-0593-3] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2007] [Accepted: 02/05/2008] [Indexed: 01/18/2023]
Abstract
UNLABELLED The vertebral trabecular bone has a complex three-dimensional (3D) microstructure, with inhomogeneous morphology. A thorough understanding of regional variations in the microstructural properties is crucial for evaluating age- and gender-related bone loss of the vertebra, and may help us to gain more insight into the mechanism of the occurrence of vertebral osteoporosis and the related fracture risks. INTRODUCTION The aim of this study was to identify regional differences in 3D microstructure of vertebral trabecular bone with age and gender, using micro-computed tomography (micro-CT) and scanning electron microscopy (SEM). METHODS We used 56 fourth lumbar vertebral bodies from 28 women and men (57-98 years of age) cadaver donors. The subjects were chosen to give an even age and gender distribution. Both women and men were divided into three age groups, 62-, 77- and 92-year-old groups. Five cubic specimens were prepared from anterosuperior, anteroinferior, central, posterosuperior and posteroinferior regions at sagittal section. Bone specimens were examined by using micro-CT and SEM. RESULTS Reduced bone volume (BV/TV), trabecular number (Tb.N) and connectivity density (Conn.D), and increased structure model index (SMI) were found between ages 62 and 77 years, and between ages 77 and 92 years. As compared with women, men had higher Tb.N in the 77-year-old group and higher Conn.D in the 62- and 77-year-old groups. The central and anterosuperior regions had lower BV/TV and Conn.D than their corresponding posteroinferior region. Increased resorbing surfaces, perforated or disconnected trabeculae and microcallus formations were found with age. CONCLUSION Vertebral trabeculae are microstructurally heterogeneous. Decreases in BV/TV and Conn.D with age are similar in women and men. Significant differences between women and men are observed at some microstructural parameters. Age-related vertebral trabecular bone loss may be caused by increased activity of resorption. These findings illustrate potential mechanisms underlying vertebral fractures.
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Cheung KH, Kashyap V, Luciano JS, Chen H, Wang Y, Stephens S. Semantic mashup of biomedical data. J Biomed Inform 2008; 41:683-6. [PMID: 18703163 PMCID: PMC3742004 DOI: 10.1016/j.jbi.2008.08.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2008] [Revised: 07/30/2008] [Accepted: 08/05/2008] [Indexed: 12/24/2022]
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2264
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Dunn J, Magee EW, Shepherd R, Chen H, Hansen SB, Moon SJ, Brown GV, Gu MF, Beiersdorfer P, Purvis MA. High resolution soft x-ray spectroscopy of low Z K-shell emission from laser-produced plasmas. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2008; 79:10E314. [PMID: 19044476 DOI: 10.1063/1.2968704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A large radius, R=44.3 m, high resolution grating spectrometer (HRGS) with 2400 lines/mm variable line spacing has been designed for laser-produced plasma experiments conducted at the Lawrence Livermore National Laboratory Jupiter Laser Facility. The instrument has been run with a low-noise, charge-coupled device detector to record high signal-to-noise spectra in the 10-50 A wavelength range. The instrument can be run with a 10-20 microm wide slit to achieve the best spectral resolving power, approaching 1000 and similar to crystal spectrometers at 12-20 A, or in slitless operation with a small symmetrical emission source. We describe preliminary spectra emitted from various H-like and He-like low Z ion plasmas heated by 100-500 ps (full width at half maximum), 527 nm wavelength laser pulses. This instrument can be developed as a useful spectroscopy platform relevant to laboratory-based astrophysics as well as high energy density plasma studies.
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Xu X, Chen H, Fujimura T, Kawasaki S. Fine mapping of a strong QTL of field resistance against rice blast, Pikahei-1(t), from upland rice Kahei, utilizing a novel resistance evaluation system in the greenhouse. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2008; 117:997-1008. [PMID: 18758744 DOI: 10.1007/s00122-008-0839-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2008] [Accepted: 06/21/2008] [Indexed: 05/20/2023]
Abstract
Field resistances (FR) against rice blast are highly evaluated by breeders for their durability, in contrast to the conspicuous but often less durable true resistances. However, lack of efficient systems for evaluation of resistance has delayed their practical application. Kahei, an upland domestic cv., is known for its very high FR against rice blast. We fine-mapped its highest quantitative trait loci (QTL), qBFR4-1, using residual heterozygosity of recombinant inbred lines (RILs) and our semi-natural rice blast inoculation/evaluation system in the greenhouse, with comparable accuracy to the true resistance genes. This system enabled reproducible high-density infection, and consequently allowed quantification of the resistance level in individual plants. The target region was first narrowed down to about 1 Mb around at 32 Mb from the top of chromosome 4 in the Nipponbare genome, with the upland evaluation system assessing the F7 generation of Koshihikari (lowland, FR: very weak) x Kahei (upland, FR: very strong) RILs. Then, F9 plants (4,404)--siblings of hetero F8 plants at the region--were inoculated with rice blast in a greenhouse using the novel inoculation system, and individual resistance levels were diagnosed for fine QTL analysis and graphical genotyping. Thus, the resistance gene was fine-mapped within 300 kb at 31.2-31.5 Mb on chromosome 4, and designated Pikahei-1(t). By annotation analysis, seven resistance gene analog (RGA) ORFs of nucleotide-binding-site and leucine-rich-repeat (NBS-LRR)-type were found in the center of the region as the most likely candidate counterparts of the resistance gene. This is similar in structure to the recently reported Pik cluster region, suggesting that most of the other dominant QTLs of the FRs may have similar RGA structures.
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2266
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Chen H, Perchonok M. US Governmental Interagency Programs, Opportunities, and Collaboration. FOOD SCI TECHNOL INT 2008. [DOI: 10.1177/1082013208098817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Improving the quality, value, and safety of national food supplies is the common mission of several Federal agencies. Under different authorities, these agencies conduct basic and applied research, develop curriculum at higher educational institutions, and disseminate new scientific knowledge about food processing, formulation, and preservation to a broad range of stakeholders. Emerging food processing technologies, including various thermal and nonthermal processes, as well as chemical processes, have received increased attention and investment in recent years. Some agencies dealing with Emerging Technologies include the Cooperative State Research, Education, and Extension Service (CSREES), Agricultural Research Service (ARS), and Food Safety Inspection Service (FSIS), and all of the United States Department of Agriculture (USDA). The U.S. Army Natick Research Center of Department of Defense (DOD), National Aeronautics and Space Administration (NASA), and Food and Drug Administration (FDA) of Department of Human Health Service (DHHS) also are involved in this research area. These agencies have their vision, mission, strategic goals, and current programs and activities related to emerging food processing technologies. The synergy of effective collaboration and cooperation among all stakeholders is the key to generating an impact greater than the simple sum of all.
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Li M, Lan X, Chen H, Zhang L, Jing Y, Ren G, Wei T, Wang X. The novel missense mutation of goat LHX4 gene. Small Rumin Res 2008. [DOI: 10.1016/j.smallrumres.2008.06.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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2268
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Morris M, Chen H, Shiraev T. Isocaloric versus hypercaloric fat intake: Differential impact on hypothalamic NPY, POMC, glucose tolerance and adiposity in the rat. Appetite 2008. [DOI: 10.1016/j.appet.2008.04.170] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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2269
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Fang HY, Cai QG, Chen H, Li QY. Effect of rainfall regime and slope on runoff in a gullied loess region on the Loess Plateau in China. ENVIRONMENTAL MANAGEMENT 2008; 42:402-411. [PMID: 18427882 DOI: 10.1007/s00267-008-9122-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2007] [Revised: 01/06/2008] [Accepted: 03/17/2008] [Indexed: 05/26/2023]
Abstract
Runoff was measured from seven plots with different slopes nested in Tuanshangou catchment on the Loess Plateau to study effect of slopes on runoff in relation to rainfall regimes. Based on nine years of field observation and K-mean clusters, 84 rainfall events were grouped into three rainfall regimes. Rainfall regime A is the group of events with strong rainfall intensity, high frequency, and short duration. Rainfall regime C consists of events with low intensity, long duration, and infrequent occurrence. Rainfall regime B is the aggregation of events of medium intensity and medium duration, and less frequent occurrence. The following results were found: (1) Different from traditional studies, runoff coefficient neither decreased nor increased, but presented peak value on the slope surfaces; (2) For individual plot, runoff coefficients induced by rainfall regime A were the highest, and those induced by rainfall regime C were the lowest; Downslope, the runoff coefficients induced by three rainfall regimes presented the same changing trend, although the peak value induced by regime A occurred on a shorter slope length compared to those by regime B and C; (3) Scale effect on runoff induced by rainfall regime A was the least, and that induced by rainfall regime C was the largest. These results can be explained by the interactions of crusting, soil moisture content, slope length and gradient, and erosion units, etc., in the context of different rainfall regimes.
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Boggula R, Lorenz F, Chen H, Gansemer C, Wertz H, Giuliacci A, Brusasco C, Mueller L, Wenz F. Commissioning of a System to Correlate Dose Measurements to Patients Anatomy. Int J Radiat Oncol Biol Phys 2008. [DOI: 10.1016/j.ijrobp.2008.06.354] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Jaboin J, Perez C, Chen H, Wills M, Lu B. MMP7 Gene Polymorphism Associated with Increased Local Recurrence Risk in Patients Receiving Radical Prostatectomy for Early-stage Prostate Cancer: Implications for Postoperative Radiation Therapy. Int J Radiat Oncol Biol Phys 2008. [DOI: 10.1016/j.ijrobp.2008.06.443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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2272
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Zhai W, Chen H, Yan H, Yan C, Wang G, Zhu L. Analysis and location of a rice BAC clone containing telomeric DNA sequences. SCIENCE IN CHINA. SERIES C, LIFE SCIENCES 2008; 42:68-73. [PMID: 18726500 DOI: 10.1007/bf02881750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/1998] [Indexed: 10/22/2022]
Abstract
BAC2, a rice BAC clone containing (TTTAGGG)(n) homologous sequences, was analyzed by Southern hybridization and DNA sequencing of its subclones. It was disclosed that there were many tandem repeated satellite DNA sequences, called TA352, as well as simple tandem repeats consisting of TTTAGGG or its variant within the BAC2 insert. A 0. 8 kb (TTTAGGG)(n)-containing fragment in BAC2 was mapped in the telomere regions of at least 5 pairs of rice chromosomes by using fluorescencein situ hybridization (FISH). By RFLP analysis of low copy sequences the BAC2 clone was localized in one terminal region of chromosome 6. All the results strongly suggest that the telomeric DNA sequences of rice are TTTAGGG or its variant, and the linked satellite DNA TA352 sequences belong to telomere-associated sequences.
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Huang XJ, Liu DH, Liu KY, Xu LP, Chen H, Han W, Chen YH, Wang JZ, Gao ZY, Zhang YC, Jiang Q, Shi HX, Lu DP. Erratum: Haploidentical hematopoietic stem cell transplantation without in vitro T-cell depletion for the treatment of hematological malignancies. Bone Marrow Transplant 2008. [DOI: 10.1038/bmt.2008.216] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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2274
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Liu RH, Wu G, Wu T, Fang DF, Chen H, Li SY, Liu K, Xie YL, Wang XF, Yang RL, Ding L, He C, Feng DL, Chen XH. Anomalous transport properties and phase diagram of the FeAs-based SmFeAsO1-xFx superconductors. PHYSICAL REVIEW LETTERS 2008; 101:087001. [PMID: 18764649 DOI: 10.1103/physrevlett.101.087001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2008] [Indexed: 05/26/2023]
Abstract
We report the detailed phase diagram and anomalous transport properties of Fe-based high-T_{c} superconductors SmFeAsO1-xFx. It is found that superconductivity emerges at x approximately 0.07, and optimal doping takes place in the x approximately 0.20 sample with the highest T_{c} approximately 54 K. T_{c} increases monotonically with doping; the anomaly in resistivity from structural phase or spin-density-wave order is rapidly suppressed, suggesting a quantum critical point around x approximately 0.14. As manifestations, a linear temperature dependence of the resistivity shows up at high temperatures in the x<0.14 regime but at low temperatures just above T_{c} in the x>0.14 regime; a drop in carrier density evidenced by a pronounced rise in the Hall coefficient is observed below the temperature of the anomaly peak in resistivity. A scaling behavior is observed between the Hall angle and temperature: cottheta_{H} proportional, variantT;{1.5} for all samples with different x in SmFeAsO1-xFx system.
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Zink T, Deng Z, Chen H, Yu L, Liu FT, Liu GY. High-resolution three-dimensional imaging of the rich membrane structures of bone marrow-derived mast cells. Ultramicroscopy 2008; 109:22-31. [PMID: 18790570 DOI: 10.1016/j.ultramic.2008.07.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2007] [Revised: 05/01/2008] [Accepted: 07/23/2008] [Indexed: 10/21/2022]
Abstract
Atomic force microscopy (AFM) enables high-resolution three-dimensional (3D) imaging of cultured bone marrow-derived mast cells. Cells were immobilized by a quick centrifugation and fixation to preserve their transient cellular morphologies followed by AFM characterization in buffer. This "fix-and-look" approach preserves the structural integrity of individual cells. Well-known membrane morphologies, such as ridges and microvilli, are visualized, consistent with prior electron microscopy observations. Additional information including the 3D measurements of these characteristic features are attained from AFM topographs. Filopodia and lamellopodia, associated with cell spreading, were captured and visualized in three dimensions. New morphologies are also revealed, such as high-density ridges and micro-craters. This investigation demonstrates that the "fix-and-look" approach followed by AFM imaging provides an effective means to characterize the membrane structure of hydrated cells with high resolution. The quantitative imaging and measurements pave the way for systematic correlation of membrane structural features with the biological status of individual cells.
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