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Shao K, Deng HM, Chen YT, Zhou HJ, Yan GX. Screening and identification of aerobic denitrifiers. ACTA ACUST UNITED AC 2016. [DOI: 10.1088/1755-1315/39/1/012049] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Jiang H, Fu XG, Chen YT. Serum level of endothelial cell-specific molecule-1 and prognosis of colorectal cancer. GENETICS AND MOLECULAR RESEARCH 2015; 14:5519-26. [PMID: 26125749 DOI: 10.4238/2015.may.25.3] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
We evaluated the clinical significance and explored the prognostic value of serum endothelial cell-specific molecule-1 (ESM-1) expression in colorectal cancer (CRC) in a Chinese population. Serum samples were obtained from 89 CRC patients undergoing surgical treatment and 90 healthy volunteers (control group). ESM-1 levels in serum samples from CRC patients and controls were measured using a sandwich enzyme-linked immunosorbent assay. Overall survival was analyzed by the log-rank test, and survival curves were plotted according to the Kaplan-Meier method. Univariate Cox regression was performed on each clinical covariate to examine its influence on patient survival. Final multivariate models were based on step-wise addition. Serum ESM-1 expression levels were significantly higher in patients with CRC (66.81 ± 22.97 pg/mL) than in healthy volunteers (31.50 ± 16.81 pg/mL, P = 0.012). Expression levels of ESM-1 in CRC patients were significantly correlated with histological differentiation (P = 0.004), TNM stage (P = 0.007), depth of tumor invasion (P = 0.02), and lymph node metastasis (P = 0.001). Kaplan-Meier survival curves revealed that the overall survival was significantly lower in patients with high ESM-1 levels than in those with low levels (29.43 vs 61.20%, P = 0.0166). Multivariate analysis confirmed that the hazard risk of death was significantly higher in patients with high serum ESM-1 expression compared with low expression (hazard risk = 4.09, 95% confidence interval: 2.27-10.88, P < 0.001). Detection of ESM-1 levels in the serum may serve as a tumor biomarker for assessing prognosis in CRC.
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Goh SY, Ang SB, Bee YM, Chen YT, Gardner DS, Ho ET, Adaikan K, Lee YC, Lee CH, Lim FS, Lim HB, Lim SC, Seow J, Soh AW, Sum CF, Tai ES, Thai AC, Wong TY, Yap F. Ministry of Health Clinical Practice Guidelines: Diabetes Mellitus. Singapore Med J 2015; 55:334-47. [PMID: 25017409 DOI: 10.11622/smedj.2014079] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The Ministry of Health (MOH) have updated the clinical practice guidelines on Diabetes Mellitus to provide doctors and patients in Singapore with evidence-based treatment for diabetes mellitus. This article reproduces the introduction and executive summary (with recommendations from the guidelines) from the MOH clinical practice guidelines on Diabetes Mellitus, for the information of SMJ readers. Chapters and page numbers mentioned in the reproduced extract refer to the full text of the guidelines, which are available from the Ministry of Health website: http://www.moh.gov.sg/content/moh_web/healthprofessionalsportal/doctors/guidelines/cpg_medical.html. The recommendations should be used with reference to the full text of the guidelines. Following this article are multiple choice questions based on the full text of the guidelines.
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Amloy S, Karlsson KF, Eriksson MO, Palisaitis J, Persson POÅ, Chen YT, Chen KH, Hsu HC, Hsiao CL, Chen LC, Holtz PO. Excitons and biexcitons in InGaN quantum dot like localization centers. NANOTECHNOLOGY 2014; 25:495702. [PMID: 25410551 DOI: 10.1088/0957-4484/25/49/495702] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Indium segregation in a narrow InGaN single quantum well creates quantum dot (QD) like exciton localization centers. Cross-section transmission electron microscopy reveals varying shapes and lateral sizes in the range ∼1-5 nm of the QD-like features, while scanning near field optical microscopy demonstrates a highly inhomogeneous spatial distribution of optically active individual localization centers. Microphotoluminescence spectroscopy confirms the spectrally inhomogeneous distribution of localization centers, in which the exciton and the biexciton related emissions from single centers of varying geometry could be identified by means of excitation power dependencies. Interestingly, the biexciton binding energy (E(b)xx) was found to vary from center to center, between 3 to -22 meV, in correlation with the exciton emission energy. Negative binding energies are only justified by a three-dimensional quantum confinement, which confirms QD-like properties of the localization centers. The observed energy correlation is proposed to be understood as variations of the lateral extension of the confinement potential, which would yield smaller values of E(b)xx for reduced lateral extension and higher exciton emission energy. The proposed relation between lateral extension and E(b)xx is further supported by the exciton and the biexciton recombination lifetimes of a single QD, which suggest a lateral extension of merely ∼3 nm for a QD with strongly negative E(b)xx = -15.5 meV.
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Chen YT. Dental Care Use And Associated Factors Among People With Rheumatoid Arthritis: A Nationwide, Population-Based, Propensity Score-Matched Follow-Up Study. VALUE IN HEALTH : THE JOURNAL OF THE INTERNATIONAL SOCIETY FOR PHARMACOECONOMICS AND OUTCOMES RESEARCH 2014; 17:A613. [PMID: 27202141 DOI: 10.1016/j.jval.2014.08.2155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
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Yang JC, Yeh CH, Chen YT, Liao SC, Huang R, Liu HJ, Hung CC, Chen SH, Wu SL, Lai CH, Chiu YP, Chiu PW, Chu YH. Conduction control at ferroic domain walls via external stimuli. NANOSCALE 2014; 6:10524-10529. [PMID: 25092204 DOI: 10.1039/c4nr03300k] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Intriguing functionalities at nano-sized domain walls have recently spawned a new paradigm for developing novel nanoelectronics due to versatile characteristics. In this study, we explore a new scenario to modulate the local conduction of ferroic domain walls. Three controlling parameters, i.e., external electrical field, magnetic field and light, are introduced to the 90° domain walls (90° DWs) of BiFeO₃. Electrical modulation is realized by electrical transport, where the mobility of 90° DWs can be altered by gating voltage. We further use the ferromagnetic/antiferromagnetic coupling to reveal the inherent magnetism at the DWs. With an established magnetic nature, magnetotransport has been conducted to introduce magnetic controlling parameter, where a giant positive magnetoresistance change can be observed up to 200%. In addition, light modulated conduction, a core factor for multifunctional applications, is successfully demonstrated (current enhancement by a factor of 2 with 11 W white lamp). These results offer new insights to discover the tunability of domain wall nanoelectronics.
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Liu J, Jiang JM, Chen YT. Genetic diversity of central and peripheral populations of Toona ciliata var. pubescens, an endangered tree species endemic to China. GENETICS AND MOLECULAR RESEARCH 2014; 13:4579-90. [PMID: 25036507 DOI: 10.4238/2014.june.17.10] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Our objective was to examine the genetic diversity of central and peripheral populations of Toona ciliata var. pubescens, to elucidate whether the central-peripheral hypothesis applies to these populations. We analyzed 392 individuals from nine natural populations using eight pairs of polymorphic SSR primers. The results showed that the mean numbers of observed and expected alleles in peripheral populations were higher than in central populations. Common widespread and rare local (RL) alleles were observed in all populations. However, common local alleles were found in five populations and rare widespread alleles were only found in three. The total numbers of the four types of alleles were higher in peripheral than in central populations, and the quantity of the RL allele was obviously higher in the peripheral populations than in the central populations. Both the observed and expected heterozygosities were higher in peripheral populations compared with the central populations. The coefficient of gene differentiation of the peripheral populations was 0.3045, which was significantly higher than that of the central populations. The gene flow between central populations was greater than one, but less than one between peripheral populations. This indicates that frequent gene flow exists between central populations, while terrain and habitat fragmentation prevent gene flow between peripheral populations. A Mantel test indicated that there was no relationship between genetic and geographical distance of T. ciliata var. pubescens.
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Chen YT, Yang WC, Chen TW, Lin CC. Trichosporon mucoides peritonitis in a continuous ambulatory peritoneal dialysis patient. Perit Dial Int 2014; 33:341-2. [PMID: 23660618 DOI: 10.3747/pdi.2012.00146] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Chen YT, Rabilloud M, Thiolet JM, Coignard B, Metzger MH. Benchmarking French regions according to their prevalence of healthcare-associated infections. Int J Qual Health Care 2013; 25:555-63. [PMID: 23929913 DOI: 10.1093/intqhc/mzt050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVE To propose an original method of benchmarking regions based on their prevalence of healthcare-associated infections (HAIs) and to identify regions with unusual results. DESIGN To study between-region variability with a three-level hierarchical logistic regression model and a Bayesian non-parametric method. SETTING French 2006 national HAIs point prevalence survey. PARTICIPANTS A total of 336 858 patients from 2289 healthcare facilities in 27 regions. Patients with an imported HAI (1% of the data, 20.7% of infected patients), facilities with <5 patients and patients who had at least one missing value for the variables taken into account were excluded (5.0% of patients). MAIN OUTCOME MEASURE Binary outcome variable indicates whether a given patient was infected. RESULTS Two clusters of regions were identified: one cluster of five regions had a lower adjusted prevalence than the other one of 22 regions, while no region with unusually high prevalence could be identified. Nevertheless, the degree of heterogeneity of odds ratios between facilities for facility-specific effects of use of invasive devices was more important in some regions than in others. CONCLUSIONS The adjusted regional prevalence of HAIs can serve as an adequate benchmark to identify regions with concerning results. Although no outlier regions were identified, the proposed approach could be applied to the data of the 2012 national survey to benchmark regional healthcare policies. The estimation of facility-specific effects of use of invasive devices may orient future regional action plans.
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Tan G, De Roza J, Chen YT, How CH. Diabetes mellitus: the first visit. Singapore Med J 2013; 54:377-80; quiz 381. [DOI: 10.11622/smedj.2013137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Li S, Liu ZC, Yin SJ, Chen YT, Yu HL, Zeng J, Zhang Q, Zhu F. Human endogenous retrovirus W family envelope gene activates the small conductance Ca2+-activated K+ channel in human neuroblastoma cells through CREB. Neuroscience 2013; 247:164-74. [PMID: 23727510 DOI: 10.1016/j.neuroscience.2013.05.033] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Revised: 05/17/2013] [Accepted: 05/17/2013] [Indexed: 11/25/2022]
Abstract
Numerous studies have shown that human endogenous retrovirus W family (HERV-W) envelope gene (env) is related to various diseases but the underlying mechanism has remained poorly understood. Our previous study showed that there was abnormal expression of HERV-W env in sera of patients with schizophrenia. In this paper, we reported that overexpression of the HERV-W env elevated the levels of small conductance Ca(2+)-activated K(+) channel protein 3 (SK3) in human neuroblastoma cells. Using a luciferase reporter system and RNA interference method, we found that functional cAMP response element site was required for the expression of SK3 triggered by HERV-W env. In addition, it was also found that the SK3 channel was activated by HERV-W env. Further study indicated that cAMP response element-binding protein (CREB) was required for the activation of the SK3 channel. Thus, a novel signaling mechanism of how HERV-W env influences neuronal activity and contributes to mental illnesses such as schizophrenia was proposed.
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Wang SJ, Sui ML, Chen YT, Lu QH, Ma E, Pei XY, Li QZ, Hu HB. Microstructural fingerprints of phase transitions in shock-loaded iron. Sci Rep 2013; 3:1086. [PMID: 23336068 PMCID: PMC3548189 DOI: 10.1038/srep01086] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2012] [Accepted: 12/11/2012] [Indexed: 11/25/2022] Open
Abstract
The complex structural transformation in crystals under static pressure or shock loading has been a subject of long-standing interest to materials scientists and physicists. The polymorphic transformation is of particular importance for iron (Fe), due to its technological and sociological significance in the development of human civilization, as well as its prominent presence in the earth's core. The martensitic transformation α→ε (bcc→hcp) in iron under shock-loading, due to its reversible and transient nature, requires non-trivial detective work to uncover its occurrence. Here we reveal refined microstructural fingerprints, needle-like colonies and three sets of {112}<111> twins with a threefold symmetry, with tell-tale features that are indicative of two sequential martensitic transformations in the reversible α→ε phase transition, even though no ε is retained in the post-shock samples. The signature orientation relationships are consistent with previously-proposed transformation mechanisms, and the unique microstructural fingerprints enable a quantitative assessment of the volume fraction transformed.
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Wei X, Qiao WH, Chen YT, Wang RS, Cao LR, Zhang WX, Yuan NN, Li ZC, Zeng HL, Yang QW. Domestication and geographic origin of Oryza sativa in China: insights from multilocus analysis of nucleotide variation of O. sativa and O. rufipogon. Mol Ecol 2012; 21:5073-87. [PMID: 22989375 DOI: 10.1111/j.1365-294x.2012.05748.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2011] [Revised: 07/02/2012] [Accepted: 07/10/2012] [Indexed: 11/28/2022]
Abstract
Previous studies have indicated that China is one of the domestication centres of Asian cultivated rice (Oryza sativa), and common wild rice (O. rufipogon) is the progenitor of O. sativa. However, the number of domestication times and the geographic origin of Asian cultivated rice in China are still under debate. In this study, 100 accessions of Asian cultivated rice and 111 accessions of common wild rice in China were selected to examine the relationship between O. sativa and O. rufipogon and thereby infer the domestication and evolution of O. sativa in China through sequence analyses of six gene regions, trnC-ycf6 in chloroplast genomes, cox3 in mitochondrial genomes and ITS, Ehd1, Waxy, Hd1 in nuclear genomes. The results indicated that the two subspecies of O. sativa (indica and japonica) were domesticated independently from different populations of O. rufipogon with gene flow occurring later from japonica to indica; Southern China was the genetic diversity centre of O. rufipogon, and the Pearl River basin near the Tropic of Cancer was the domestication centre of O. sativa in China.
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Wang MC, Chen YT, Chen SH, Chang Chien SW, Sunkara SV. Phytoremediation of pyrene contaminated soils amended with compost and planted with ryegrass and alfalfa. CHEMOSPHERE 2012; 87:217-225. [PMID: 22245074 DOI: 10.1016/j.chemosphere.2011.12.063] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2011] [Revised: 12/21/2011] [Accepted: 12/22/2011] [Indexed: 05/31/2023]
Abstract
Ryegrass (Lolium perenne) and alfalfa (Medicago sativa) were planted in pots to remediate pyrene contaminated quartz sand (as a control group), alluvial and red soils amended with and without compost. The pyrene degradation percentages in quartz sand, alluvial soil, and red soil amended with compost (5%, w/w) and planted with ryegrass and alfalfa for 90 d growth were 98-99% and 97-99%, respectively, while those of pyrene in the corresponding treatments amended without compost but planted with ryegrass and alfalfa were 91-96% and 58-89%, respectively. Further, those of pyrene in the respective treatments amended with and without compost but unplanted were 54-77% and 51-63%, respectively. Pyrene contents in both roots and aboveground parts of ryegrass and alfalfa after 90 d growth in quartz sand and the two soils amended with or without compost were trace amounts. Statistical analyses for the parameters of ryegrass planted in red and alluvial soils including the concentrations of total water-soluble volatile low molecular weight organic acids, microbial population, pyrene degradation percentage, and spiked pyrene concentration show significant correlations at 5% and mostly 1% probability levels, by the analysis of variance. It was thus suggested that the interactions among the consortia of plant root exudates, microorganisms, and amended compost in rhizosphere soils could facilitate bioavailability of pyrene and subsequently enhance its dissipation.
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Murphy R, Green S, Ritter G, Cohen L, Ryan D, Woods W, Rubira M, Cebon J, Davis ID, Sjolander A, Kypridis A, Kalnins H, McNamara M, Moloney MB, Ackland J, Cartwright G, Rood J, Dumsday G, Healey K, Maher D, Maraskovsky E, Chen YT, Hoffman EW, Old LJ, Scott AM. Recombinant NY‐ESO‐1 Cancer Antigen: Production and Purification under cGMP Conditions. Prep Biochem Biotechnol 2010; 35:119-34. [PMID: 15881594 DOI: 10.1081/pb-200054732] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The cancer-testis antigen, NY-ESO-1, has been engineered into a bacterial expression plasmid which incorporates a His6-tag. The plasmid was transfected into E. coli strain BL21 and Master and Working cell banks generated from this expression system. Three 15-litre fermentations were performed under cGMP (code of Good Manufacturing Practice) conditions and the crude NY-ESO-1 tagged protein isolated as solubilised inclusion bodies. A three-step cGMP chromatography process (immobilised metal affinity, anion exchange, and hydrophobic interaction) was utilised to purify the protein. The purified NY-ESO-1 is being used in early stage human cancer vaccine trials in Australia and the U.S.A.
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Koeberl DD, Pinto C, Brown T, Chen YT. Gene therapy for inherited metabolic disorders in companion animals. ILAR J 2009; 50:122-7. [PMID: 19293457 DOI: 10.1093/ilar.50.2.122] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Scientists first described inborn errors of metabolism, also termed inherited disorders of metabolism, early in the 20th century and since then have determined the biochemical and genetic bases of a great number of these disorders both in humans and in an increasing number of companion animals. The availability of metabolic screening tests has advanced the biochemical and genetic characterization in affected breeds of companion animals of inherited metabolic disorders involving amino acid, carbohydrate, fatty acid, and metal metabolism. Advances in gene therapy have led to the development of new treatments for inherited disorders of metabolism, and animal models have played a critical role in this research. For example, glycogen storage disease type Ia in dogs was highly responsive to adeno-associated viral vectormediated gene therapy, which prolonged survival and for more than a year prevented hypoglycemia during fasting. Gene therapy for other glycogen storage diseases and metabolic disorders will also be feasible. The establishment of a breeding colony and the ability to sustain affected animals are critical steps toward evaluating the safety and efficacy of gene therapy with clinically relevant endpoints. The further development of gene therapy for inherited disorders of metabolism could lead to curative therapy for affected humans and animals alike.
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Nieves JW, Barrett-Connor E, Siris ES, Zion M, Barlas S, Chen YT. Calcium and vitamin D intake influence bone mass, but not short-term fracture risk, in Caucasian postmenopausal women from the National Osteoporosis Risk Assessment (NORA) study. Osteoporos Int 2008; 19:673-9. [PMID: 17999024 DOI: 10.1007/s00198-007-0501-2] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2007] [Accepted: 09/27/2007] [Indexed: 12/31/2022]
Abstract
UNLABELLED The impact of calcium and vitamin D intake on bone density and one-year fracture risk was assessed in 76,507 postmenopausal Caucasian women. Adequate calcium with or without vitamin D significantly reduced the odds of osteoporosis but not the risk of fracture in these Caucasian women. INTRODUCTION Calcium and vitamin D intake may be important for bone health; however, studies have produced mixed results. METHODS The impact of calcium and vitamin D intake on bone mineral density (BMD) and one-year fracture incidence was assessed in 76,507 postmenopausal Caucasian women who completed a dietary questionnaire that included childhood, adult, and current consumption of dairy products. Current vitamin D intake was calculated from milk, fish, supplements and sunlight exposure. BMD was measured at the forearm, finger or heel. Approximately 3 years later, 36,209 participants returned a questionnaire about new fractures. The impact of calcium and vitamin D on risk of osteoporosis and fracture was evaluated by logistic regression adjusted for multiple covariates. RESULTS Higher lifetime calcium intake was associated with reduced odds of osteoporosis (peripheral BMD T-score < or =-2.5; OR = 0.80; 95% CI 0.72, 0.88), as was a higher current calcium (OR = 0.75; (0.68, 0.82)) or vitamin D intake (OR = 0.73; 95% CI 0.0.66, 0.81). Women reported 2,205 new osteoporosis-related fractures. The 3-year risk of any fracture combined or separately was not associated with intake of calcium or vitamin D. CONCLUSIONS Thus, higher calcium and vitamin D intakes significantly reduced the odds of osteoporosis but not the 3-year risk of fracture in these Caucasian women.
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Chen YT, Lo TN, Chiu CW, Wang JY, Wang CL, Liu CJ, Wu SR, Jeng ST, Yang CC, Shiue J, Chen CH, Hwu Y, Yin GC, Lin HM, Je JH, Margaritondo G. Fabrication of high-aspect-ratio Fresnel zone plates by e-beam lithography and electroplating. JOURNAL OF SYNCHROTRON RADIATION 2008; 15:170-175. [PMID: 18296784 DOI: 10.1107/s0909049507063510] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2007] [Accepted: 11/26/2007] [Indexed: 05/25/2023]
Abstract
The fabrication of gold Fresnel zone plates, by a combination of e-beam lithography and electrodeposition, with a 30 nm outermost zone width and a 450 nm-thick structure is described. The e-beam lithography process was implemented with a careful evaluation of applied dosage, tests of different bake-out temperatures and durations for the photoresist, and the use of a developer without methylisobutylketone. Electrodeposition with a pulsed current mode and with a specially designed apparatus produced the desired high-aspect-ratio nanostructures. The fabricated zone plates were examined by electron microscopy and their performances were assessed using a transmission X-ray microscope. The results specifically demonstrated an image resolution of 40 nm.
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Lee DN, Liu SR, Chen YT, Wang RC, Lin SY, Weng CF. Effects of diets supplemented with organic acids and nucleotides on growth, immune responses and digestive tract development in weaned pigs. J Anim Physiol Anim Nutr (Berl) 2008; 91:508-18. [PMID: 17988355 DOI: 10.1111/j.1439-0396.2007.00684.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Sixty-eight (Experiment 1, 46 days feeding) and sixteen (Experiment 2, 21 days feeding) 21-days-old weaned pigs were allotted to four dietary treatments including control, 0.6% organic acids (OA), 0.1% nucleotides (NA) and 0.6% OA plus 0.1% NA for determining the dietary effects. In Experiment 1, OA enhanced peripheral blood mononuclear cells proliferation on day 28 and 46. The plasma immunoglobulin (Ig) A level was elevated by OA (p < 0.06) and NA (p < 0.07), respectively. In Experiment 2, NA increased plasma IgM level, and had an interactive effect with OA on ileal Peyer's patches and mesenteric lymph node lymphocyte proliferation, bile and plasma IgA levels, and jejunal crypt depth. NA elevated gastric pepsin and jejunal alkaline phosphatase activities, however, decreased ileal aminopeptidase N, sucrase or maltase activity. These results suggest that OA and NA have synergistically enhanced the gut-associated lymphocyte responses and NA modulates the digestive tract development of weaned pigs.
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Goetz DH, Choe Y, Hansell E, Chen YT, McDowell M, Jonsson CB, Roush WR, McKerrow J, Craik CS. Substrate Specificity Profiling and Identification of a New Class of Inhibitor for the Major Protease of the SARS Coronavirus,. Biochemistry 2007; 46:8744-52. [PMID: 17605471 DOI: 10.1021/bi0621415] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Severe acute respiratory syndrome (SARS) is an emerging infectious disease associated with a high rate of mortality. The SARS-associated coronavirus (SARS-CoV) has been identified as the etiological agent of the disease. Although public health procedures have been effective in combating the spread of SARS, concern remains about the possibility of a recurrence. Various approaches are being pursued for the development of efficacious therapeutics. One promising approach is to develop small molecule inhibitors of the essential major polyprotein processing protease 3Clpro. Here we report a complete description of the tetrapeptide substrate specificity of 3Clpro using fully degenerate peptide libraries consisting of all 160,000 possible naturally occurring tetrapeptides. The substrate specificity data show the expected P1-Gln P2-Leu specificity and elucidate a novel preference for P1-His containing substrates equal to the expected preference for P1-Gln. These data were then used to develop optimal substrates for a high-throughput screen of a 2000 compound small-molecule inhibitor library consisting of known cysteine protease inhibitor scaffolds. We also report the 1.8 A X-ray crystal structure of 3Clpro bound to an irreversible inhibitor. This inhibitor, an alpha,beta-epoxyketone, inhibits 3Clpro with a k3/Ki of 0.002 microM(-1) s(-1) in a mode consistent with the substrate specificity data. Finally, we report the successful rational improvement of this scaffold with second generation inhibitors. These data provide the foundation for a rational small-molecule inhibitor design effort based upon the inhibitor scaffold identified, the crystal structure of the complex, and a more complete understanding of P1-P4 substrate specificity.
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Koeberl DD, Sun B, Bird A, Chen YT, Oka K, Chan L. Efficacy of Helper-dependent Adenovirus Vector-mediated Gene Therapy in Murine Glycogen Storage Disease Type Ia. Mol Ther 2007; 15:1253-8. [PMID: 17505475 DOI: 10.1038/sj.mt.6300188] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Genetic deficiency of glucose-6-phosphatase (G6Pase) underlies glycogen storage disease type Ia (GSD-Ia, also known as von Gierke disease; MIM 232200), an autosomal recessive disorder of metabolism associated with life-threatening hypoglycemia and growth retardation. We tested whether helper-dependent adenovirus (HDAd)-mediated hepatic delivery of G6Pase would lead to prolonged survival and sustained correction of the metabolic abnormalities in G6Pase knockout (KO) mice, a model for a severe form of GSD-Ia. An HDAd vector encoding G6Pase was administered intravenously (2 or 5 x 10(12)vector particles/kg) to 2-week-old (w.o.) G6Pase-KO mice. Following HDAd vector administration survival was prolonged to a median of 7 months, in contrast to untreated affected mice that did not survive past 3 weeks of age. G6Pase levels increased more than tenfold between 3 days and 28 weeks after HDAd injection (P < 0.03). The weights of untreated 2 w.o. G6Pase-KO mice were approximately half those of their unaffected littermates, and treatment stimulated their growth to the size of wild-type mice. Severe hypoglycemia and hypercholesterolemia, which are hallmarks of GSD-Ia both in humans and in mice, were also restored to normalcy by the treatment. Glycogen accumulation in the liver was markedly reduced. The efficacy of HDAd-G6Pase treatment in reversing the physiological and biochemical abnormalities associated with GSD-Ia in affected G6Pase-KO mice justifies further preclinical evaluation in murine and canine models of GSD-Ia.
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Koeberl DD, Kishnani PS, Chen YT. Glycogen storage disease types I and II: treatment updates. J Inherit Metab Dis 2007; 30:159-64. [PMID: 17308886 PMCID: PMC2692363 DOI: 10.1007/s10545-007-0519-9] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2006] [Revised: 12/31/2006] [Accepted: 01/02/2007] [Indexed: 12/13/2022]
Abstract
Prior to 2006 therapy for glycogen storage diseases consisted primarily of dietary interventions, which in the case of glycogen storage disease (GSD) type II (GSD II; Pompe disease) remained essentially palliative. Despite improved survival and growth, long-term complications of GSD type I (GSD I) have not responded to dietary therapy with uncooked cornstarch or continuous gastric feeding. The recognized significant risk of renal disease and liver malignancy in GSD I has prompted efforts towards curative therapy, including organ transplantation, in those deemed at risk. Results of clinical trials in infantile Pompe disease with alglucosidase alfa (Myozyme) showed prolonged survival reversal of cardiomyopathy, and motor gains. This resulted in broad label approval of Myozyme for Pompe disease in 2006. Furthermore, the development of experimental therapies, such as adeno-associated virus (AAV) vector-mediated gene therapy, holds promise for the availability of curative therapy in GSD I and GSD II/Pompe disease in the future.
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Chen YT, Ding J. Lattice Monte Carlo simulation of coil-helix transition. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2005:4445-8. [PMID: 17281223 DOI: 10.1109/iembs.2005.1615453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
An improved self-avoiding lattice model was put forward to study coil-helix transition via dynamic Monte Carlo simulation. Each residue occupies eight simple lattices. By introducing a virtual-imino group and a virtual-carbonyl group, the helical period is not necessarily to be an integer. The Gö-like restriction of hydrogen bonding interaction has also been partially released. The coil-helix transition was well reproduced and consistent with the Zimm-Bragg theory. Non-native hydrogen bonding interaction seems significant around transition temperature. In characterization of a statistically helical structure, a novel correlation function was put forward and verified.
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Koeberl DD, Sun BD, Damodaran TV, Brown T, Millington DS, Benjamin DK, Bird A, Schneider A, Hillman S, Jackson M, Beaty RM, Chen YT. Erratum: Early, sustained efficacy of adeno-associated virus vector-mediated gene therapy in glycogen storage disease type Ia. Gene Ther 2007. [DOI: 10.1038/sj.gt.3302903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Hwu CM, Hsiao CF, Grove J, Hung YJ, Chuang LM, Chen YT, Curb JD, Chen YDI, Rodriguez B, Ho LT. Surrogate estimates of insulin sensitivity in subjects with hypertension. J Hum Hypertens 2007; 21:246-52. [PMID: 17230234 DOI: 10.1038/sj.jhh.1002137] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The purpose of the study is to compare surrogate estimates of insulin sensitivity with a directly measured insulin sensitivity index, steady-state plasma glucose (SSPG) from insulin suppression test (IST), in subjects with hypertension. Two hundred and twenty-eight hypertensive patients who received IST for SSPG were included for analysis. Estimates from fasting measurements alone, homeostasis model assessment for insulin resistance (HOMA-IR) and quantitative insulin sensitivity check index (QUICKI)), and indices from fasting and/or 2 h samples (ISI(0,120) and ISI(TX)) were calculated. In addition to Pearson and partial correlations, variance-component models were used to test the relationship between surrogate estimates of insulin sensitivity and SSPG. A large proportion of variance owing to covariates in the variance-component models indicated the goodness of model fit, irrespective of the independence among variables. SSPG was positively correlated with logarithmic transformation (Log) (HOMA-IR) and negatively correlated with QUICKI, Log (ISI(0,120)) and ISI(TX) (all P<0.0001). Log (ISI(0,120)) seemed to have a better correlation with SSPG (r=-0.72) than other measures in partial correlation. The proportion of variance owing to all covariates of Log (ISI(0,120)) and ISI(TX) were larger than those of Log (HOMA-IR) and QUICKI in the variance-component models. After adjustments for demographic and obesity covariates, the proportion of variance explained by Log (ISI(0,120)) were largest among the surrogate measures in the variance-component models. Our results showed that ISI(0,120) and ISI(TX) correlated better with SSPG than those used fasting measures alone (HOMA-IR and QUICKI). Log (ISI(0,120)) currently showing the strongest association with SSPG than other estimates is adaptable for use in large studies of hypertension.
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