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Lin HW, Lin CH, Chang CK, Chou CY, Chao PT, Hsu CN, Chang LY, Hsieh YW, Hung JS, Huang WL, Cho DY. Trends of Hypnotic Medication Use in A 2000-Bed Medical Center in Taiwan. VALUE IN HEALTH : THE JOURNAL OF THE INTERNATIONAL SOCIETY FOR PHARMACOECONOMICS AND OUTCOMES RESEARCH 2014; 17:A721. [PMID: 27202554 DOI: 10.1016/j.jval.2014.08.017] [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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Aguilar M, Aisa D, Alvino A, Ambrosi G, Andeen K, Arruda L, Attig N, Azzarello P, Bachlechner A, Barao F, Barrau A, Barrin L, Bartoloni A, Basara L, Battarbee M, Battiston R, Bazo J, Becker U, Behlmann M, Beischer B, Berdugo J, Bertucci B, Bigongiari G, Bindi V, Bizzaglia S, Bizzarri M, Boella G, de Boer W, Bollweg K, Bonnivard V, Borgia B, Borsini S, Boschini MJ, Bourquin M, Burger J, Cadoux F, Cai XD, Capell M, Caroff S, Casaus J, Cascioli V, Castellini G, Cernuda I, Cervelli F, Chae MJ, Chang YH, Chen AI, Chen H, Cheng GM, Chen HS, Cheng L, Chikanian A, Chou HY, Choumilov E, Choutko V, Chung CH, Clark C, Clavero R, Coignet G, Consolandi C, Contin A, Corti C, Coste B, Cui Z, Dai M, Delgado C, Della Torre S, Demirköz MB, Derome L, Di Falco S, Di Masso L, Dimiccoli F, Díaz C, von Doetinchem P, Du WJ, Duranti M, D'Urso D, Eline A, Eppling FJ, Eronen T, Fan YY, Farnesini L, Feng J, Fiandrini E, Fiasson A, Finch E, Fisher P, Galaktionov Y, Gallucci G, García B, García-López R, Gast H, Gebauer I, Gervasi M, Ghelfi A, Gillard W, Giovacchini F, Goglov P, Gong J, Goy C, Grabski V, Grandi D, Graziani M, Guandalini C, Guerri I, Guo KH, Habiby M, Haino S, Han KC, He ZH, Heil M, Hoffman J, Hsieh TH, Huang ZC, Huh C, Incagli M, Ionica M, Jang WY, Jinchi H, Kanishev K, Kim GN, Kim KS, Kirn T, Kossakowski R, Kounina O, Kounine A, Koutsenko V, Krafczyk MS, Kunz S, La Vacca G, Laudi E, Laurenti G, Lazzizzera I, Lebedev A, Lee HT, Lee SC, Leluc C, Li HL, Li JQ, Li Q, Li Q, Li TX, Li W, Li Y, Li ZH, Li ZY, Lim S, Lin CH, Lipari P, Lippert T, Liu D, Liu H, Lomtadze T, Lu MJ, Lu YS, Luebelsmeyer K, Luo F, Luo JZ, Lv SS, Majka R, Malinin A, Mañá C, Marín J, Martin T, Martínez G, Masi N, Maurin D, Menchaca-Rocha A, Meng Q, Mo DC, Morescalchi L, Mott P, Müller M, Ni JQ, Nikonov N, Nozzoli F, Nunes P, Obermeier A, Oliva A, Orcinha M, Palmonari F, Palomares C, Paniccia M, Papi A, Pedreschi E, Pensotti S, Pereira R, Pilo F, Piluso A, Pizzolotto C, Plyaskin V, Pohl M, Poireau V, Postaci E, Putze A, Quadrani L, Qi XM, Rancoita PG, Rapin D, Ricol JS, Rodríguez I, Rosier-Lees S, Rozhkov A, Rozza D, Sagdeev R, Sandweiss J, Saouter P, Sbarra C, Schael S, Schmidt SM, Schuckardt D, Schulz von Dratzig A, Schwering G, Scolieri G, Seo ES, Shan BS, Shan YH, Shi JY, Shi XY, Shi YM, Siedenburg T, Son D, Spada F, Spinella F, Sun W, Sun WH, Tacconi M, Tang CP, Tang XW, Tang ZC, Tao L, Tescaro D, Ting SCC, Ting SM, Tomassetti N, Torsti J, Türkoğlu C, Urban T, Vagelli V, Valente E, Vannini C, Valtonen E, Vaurynovich S, Vecchi M, Velasco M, Vialle JP, Wang LQ, Wang QL, Wang RS, Wang X, Wang ZX, Weng ZL, Whitman K, Wienkenhöver J, Wu H, Xia X, Xie M, Xie S, Xiong RQ, Xin GM, Xu NS, Xu W, Yan Q, Yang J, Yang M, Ye QH, Yi H, Yu YJ, Yu ZQ, Zeissler S, Zhang JH, Zhang MT, Zhang XB, Zhang Z, Zheng ZM, Zhuang HL, Zhukov V, Zichichi A, Zimmermann N, Zuccon P, Zurbach C. Electron and positron fluxes in primary cosmic rays measured with the alpha magnetic spectrometer on the international space station. PHYSICAL REVIEW LETTERS 2014; 113:121102. [PMID: 25279617 DOI: 10.1103/physrevlett.113.121102] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Indexed: 06/03/2023]
Abstract
Precision measurements by the Alpha Magnetic Spectrometer on the International Space Station of the primary cosmic-ray electron flux in the range 0.5 to 700 GeV and the positron flux in the range 0.5 to 500 GeV are presented. The electron flux and the positron flux each require a description beyond a single power-law spectrum. Both the electron flux and the positron flux change their behavior at ∼30 GeV but the fluxes are significantly different in their magnitude and energy dependence. Between 20 and 200 GeV the positron spectral index is significantly harder than the electron spectral index. The determination of the differing behavior of the spectral indices versus energy is a new observation and provides important information on the origins of cosmic-ray electrons and positrons.
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Accardo L, Aguilar M, Aisa D, Alpat B, Alvino A, Ambrosi G, Andeen K, Arruda L, Attig N, Azzarello P, Bachlechner A, Barao F, Barrau A, Barrin L, Bartoloni A, Basara L, Battarbee M, Battiston R, Bazo J, Becker U, Behlmann M, Beischer B, Berdugo J, Bertucci B, Bigongiari G, Bindi V, Bizzaglia S, Bizzarri M, Boella G, de Boer W, Bollweg K, Bonnivard V, Borgia B, Borsini S, Boschini MJ, Bourquin M, Burger J, Cadoux F, Cai XD, Capell M, Caroff S, Carosi G, Casaus J, Cascioli V, Castellini G, Cernuda I, Cerreta D, Cervelli F, Chae MJ, Chang YH, Chen AI, Chen H, Cheng GM, Chen HS, Cheng L, Chikanian A, Chou HY, Choumilov E, Choutko V, Chung CH, Cindolo F, Clark C, Clavero R, Coignet G, Consolandi C, Contin A, Corti C, Coste B, Cui Z, Dai M, Delgado C, Della Torre S, Demirköz MB, Derome L, Di Falco S, Di Masso L, Dimiccoli F, Díaz C, von Doetinchem P, Du WJ, Duranti M, D'Urso D, Eline A, Eppling FJ, Eronen T, Fan YY, Farnesini L, Feng J, Fiandrini E, Fiasson A, Finch E, Fisher P, Galaktionov Y, Gallucci G, García B, García-López R, Gast H, Gebauer I, Gervasi M, Ghelfi A, Gillard W, Giovacchini F, Goglov P, Gong J, Goy C, Grabski V, Grandi D, Graziani M, Guandalini C, Guerri I, Guo KH, Haas D, Habiby M, Haino S, Han KC, He ZH, Heil M, Henning R, Hoffman J, Hsieh TH, Huang ZC, Huh C, Incagli M, Ionica M, Jang WY, Jinchi H, Kanishev K, Kim GN, Kim KS, Kirn T, Kossakowski R, Kounina O, Kounine A, Koutsenko V, Krafczyk MS, Kunz S, La Vacca G, Laudi E, Laurenti G, Lazzizzera I, Lebedev A, Lee HT, Lee SC, Leluc C, Levi G, Li HL, Li JQ, Li Q, Li Q, Li TX, Li W, Li Y, Li ZH, Li ZY, Lim S, Lin CH, Lipari P, Lippert T, Liu D, Liu H, Lolli M, Lomtadze T, Lu MJ, Lu YS, Luebelsmeyer K, Luo F, Luo JZ, Lv SS, Majka R, Malinin A, Mañá C, Marín J, Martin T, Martínez G, Masi N, Massera F, Maurin D, Menchaca-Rocha A, Meng Q, Mo DC, Monreal B, Morescalchi L, Mott P, Müller M, Ni JQ, Nikonov N, Nozzoli F, Nunes P, Obermeier A, Oliva A, Orcinha M, Palmonari F, Palomares C, Paniccia M, Papi A, Pauluzzi M, Pedreschi E, Pensotti S, Pereira R, Pilastrini R, Pilo F, Piluso A, Pizzolotto C, Plyaskin V, Pohl M, Poireau V, Postaci E, Putze A, Quadrani L, Qi XM, Rancoita PG, Rapin D, Ricol JS, Rodríguez I, Rosier-Lees S, Rossi L, Rozhkov A, Rozza D, Rybka G, Sagdeev R, Sandweiss J, Saouter P, Sbarra C, Schael S, Schmidt SM, Schuckardt D, Schulz von Dratzig A, Schwering G, Scolieri G, Seo ES, Shan BS, Shan YH, Shi JY, Shi XY, Shi YM, Siedenburg T, Son D, Spada F, Spinella F, Sun W, Sun WH, Tacconi M, Tang CP, Tang XW, Tang ZC, Tao L, Tescaro D, Ting SCC, Ting SM, Tomassetti N, Torsti J, Türkoğlu C, Urban T, Vagelli V, Valente E, Vannini C, Valtonen E, Vaurynovich S, Vecchi M, Velasco M, Vialle JP, Vitale V, Volpini G, Wang LQ, Wang QL, Wang RS, Wang X, Wang ZX, Weng ZL, Whitman K, Wienkenhöver J, Wu H, Wu KY, Xia X, Xie M, Xie S, Xiong RQ, Xin GM, Xu NS, Xu W, Yan Q, Yang J, Yang M, Ye QH, Yi H, Yu YJ, Yu ZQ, Zeissler S, Zhang JH, Zhang MT, Zhang XB, Zhang Z, Zheng ZM, Zhou F, Zhuang HL, Zhukov V, Zichichi A, Zimmermann N, Zuccon P, Zurbach C. High statistics measurement of the positron fraction in primary cosmic rays of 0.5-500 GeV with the alpha magnetic spectrometer on the international space station. PHYSICAL REVIEW LETTERS 2014; 113:121101. [PMID: 25279616 DOI: 10.1103/physrevlett.113.121101] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Indexed: 06/03/2023]
Abstract
A precision measurement by AMS of the positron fraction in primary cosmic rays in the energy range from 0.5 to 500 GeV based on 10.9 million positron and electron events is presented. This measurement extends the energy range of our previous observation and increases its precision. The new results show, for the first time, that above ∼200 GeV the positron fraction no longer exhibits an increase with energy.
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Pan WC, Lin CH, Dai SA. High-performance segmented polyurea by transesterification of diphenyl carbonates with aliphatic diamines. ACTA ACUST UNITED AC 2014. [DOI: 10.1002/pola.27302] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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80
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Chuang KS, Lu JC, Lin HH, Dong SL, Yang HJ, Shih CT, Lin CH, Yao WJ, Ni YC, Jan ML, Chang SJ. Improvements on a patient-specific dose estimation system in nuclear medicine examination. RADIATION PROTECTION DOSIMETRY 2014; 158:1-7. [PMID: 23901136 DOI: 10.1093/rpd/nct186] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The purpose of this paper is to develop a patient-specific dose estimation system in nuclear medicine examination. A dose deposition routine to store the deposited energy of the photons during their flights was embedded in the widely used SimSET Monte Carlo code and a user-friendly interface for reading PET and CT images was developed. Dose calculated on ORNL phantom was used to validate the accuracy of this system. The ratios of S value for (99m)Tc, (18)F and (131)I computed by this system to those obtained with OLINDA for various organs were ranged from 0.93 to 1.18, which were comparable to that obtained from MCNPX2.6 code (0.88-1.22). Our system developed provides opportunity for tumor dose estimation which cannot be known from the MIRD. The radiation dose can provide useful information in the amount of radioisotopes to be administered in radioimmunotherapy.
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Wang CF, Kuo SW, Lin CH, Chen HG, Liao CS, Hung PR. Benzoxazine as a reactive noncovalent dispersant for carbon nanotubes. RSC Adv 2014. [DOI: 10.1039/c4ra04728a] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Benzoxazines can be used as a reactive noncovalent dispersant for carbon nanotubes (CNTs). The benzoxazine coatings improved the compatibility of the CNTs with various organic solvents and retained their reactivity.
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Dioguardi AP, Crocker J, Shockley AC, Lin CH, Shirer KR, Nisson DM, Lawson MM, apRoberts-Warren N, Canfield PC, Bud'ko SL, Ran S, Curro NJ. Coexistence of cluster spin glass and superconductivity in Ba(Fe(1-x)Co(x))2As2 for 0.060≤x≤0.071. PHYSICAL REVIEW LETTERS 2013; 111:207201. [PMID: 24289706 DOI: 10.1103/physrevlett.111.207201] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Revised: 09/24/2013] [Indexed: 06/02/2023]
Abstract
We present 75As nuclear magnetic resonance data from measurements of a series of Ba(Fe(1-x)Co(x))2As2 crystals with 0.00≤x≤0.075 that reveals the coexistence of frozen antiferromagnetic domains and superconductivity for 0.060≤x≤0.071. Although bulk probes reveal no long range antiferromagnetic order beyond x=0.06, we find that the local spin dynamics reveal no qualitative change across this transition. The characteristic domain sizes vary by more than an order of magnitude, reaching a maximum variation at x=0.06. This inhomogeneous glassy dynamics may be an intrinsic response to the competition between superconductivity and antiferromagnetism in this system.
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Lin CH, Zhang W, Ng TW, Zhang D, Jiang J, Pulikkottil B, Lakkis F, Gorantla VS, Lee WPA, Brandacher G, Zheng XX. Vascularized osteomyocutaneous allografts are permissive to tolerance by induction-based immunomodulatory therapy. Am J Transplant 2013; 13:2161-8. [PMID: 23718897 DOI: 10.1111/ajt.12275] [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: 04/12/2012] [Revised: 03/27/2013] [Accepted: 03/28/2013] [Indexed: 01/25/2023]
Abstract
Vascularized composite allografts (VCAs) are unique among transplanted organs in that they are composed of multiple tissues with disparate antigenic and immunologic properties. As the predominant indications for VCAs are non-life-threatening conditions, there is an immediate need to develop tolerance induction strategies and to elucidate the mechanisms of VCA rejection and tolerance using VCA-specific animal models. In this study, we explore the effects of in vitro induced donor antigen-specific CD4(-) CD8(-) double negative (DN) Treg-based therapy, in a fully MHC mismatched mouse VCA such as a vascularized osteomyocutaneous as compared to a non-VCA such as a full thickness skin (FTS) transplantation model to elucidate the unique features of VCA rejection and tolerance. We demonstrate that combined therapy with antigen-induced CD4 derived DN Tregs and a short course of anti-lymphocyte serum, rapamycin and IL-2/Fc fusion protein results in donor-specific tolerance to VCA, but not FTS allografts. Macrochimerism was detected in VCA but not FTS allograft recipients up to >60 days after transplantation. Moreover, a significant increase of CD4(+) Foxp3(+) Tregs was found in the peripheral blood of tolerant VCA recipients. These data suggest that VCA are permissive to tolerance induced by DN Treg-based induction therapy.
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84
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Lin CH, Li CH, Liao PL, Tse LS, Huang WK, Cheng HW, Cheng YW. Silibinin inhibits VEGF secretion and age-related macular degeneration in a hypoxia-dependent manner through the PI-3 kinase/Akt/mTOR pathway. Br J Pharmacol 2013; 168:920-31. [PMID: 23004355 DOI: 10.1111/j.1476-5381.2012.02227.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Revised: 08/19/2012] [Accepted: 09/06/2012] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND AND PURPOSE Hypoxia-mediated neovascularization plays an important role in age-related macular degeneration (AMD). There are few animal models or effective treatments for AMD. Here, we investigated the effects of the flavonoid silibinin on hypoxia-induced angiogenesis in a rat AMD model. EXPERIMENTAL APPROACH Retinal pigmented epithelial (RPE) cells were subjected to hypoxia in vitro and the effects of silibinin on activation of key hypoxia-induced pathways were examined by elucidating the hypoxia-inducible factor-1 alpha (HIF-1α) protein level by Western blot. A rat model of AMD was developed by intravitreal injection of VEGF in Brown Norway rats, with or without concomitant exposure of animals to hypoxia. Animals were treated with oral silibinin starting at day 7 post-VEGF injection and AMD changes were followed by fluorescein angiography on days 14 and 28 post-injection. KEY RESULTS Silibinin pretreatment of RPE cells increased proline hydroxylase-2 expression, inhibited HIF-1α subunit accumulation, and inhibited VEGF secretion. Silibinin-induced HIF-1α and VEGF down-regulation required suppression of hypoxia-induced phosphatidylinositol 3-kinase/Akt/mammalian target of rapamycin (mTOR) pathway. In the rat model of AMD, silibinin administration prevented VEGF- and VEGF plus hypoxia-induced retinal oedema and neovascularization. CONCLUSION AND IMPLICATIONS The effects of silibinin, both in vitro and in vivo, support its potential as a therapeutic for the prevention of neovascular AMD.
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Siao YY, Shau SM, Hu SH, Lee RH, Lin CH, Wu JY, Jeng RJ. Nonlinear optical hyperbranched polyaspartimide/montmorillonite nanocomposites based on reactive fluorine- or phosphorous-containing organoclays. POLYMER 2013. [DOI: 10.1016/j.polymer.2013.05.040] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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86
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Tseng LM, Hsu NC, Chen SC, Lu YS, Lin CH, Chang DY, Li H, Lin YC, Chang HK, Chao TC, Ouyang F, Hou MF. Distant metastasis in triple-negative breast cancer. Neoplasma 2013; 60:290-4. [PMID: 23373998 DOI: 10.4149/neo_2013_038] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Triple-negative breast cancer (TNBC) relapses more frequently than hormone receptor-positive subtypes and is often associated with poor outcomes. This retrospective study reviewed the pattern of distant metastasis with regard to survival in patients with TNBC. A total of 205 TNBC patients were analyzed. TNBC patients with lung metastases had the longest median post-metastatic OS (with 95% confidence interval) of 16.6 (10.3-22.9) months, followed by the bone, 16.3 (11.7-20.8) months, the liver, 8.9 (3.5-14.4) months, the pleura, 7.5 (2.8-12.3) months, and the brain, 4.3 (0.6-8.0) months. Kaplan-Meier plots indicated that TNBC patients with metastatic spread to brain, liver, and pleural had poorer post-metastatic OS rate than patients with lung metastases (p = 0.001, 0.004, and 0.029, respectively). Moreover, brain and liver metastases correlated significantly with poorer post-metastatic OS as compared to bone metastasis (p = 0.004 and 0.011, respectively). Route of first metastasis correlated significantly with survival of TNBC patients with brain metastases being the poorest survival indicator, followed by metastases to liver, pleura, bone, and lung.
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Chen LH, Lin CH, Chung KR. A nonribosomal peptide synthetase mediates siderophore production and virulence in the citrus fungal pathogen Alternaria alternata. MOLECULAR PLANT PATHOLOGY 2013; 14:497-505. [PMID: 23438010 PMCID: PMC6638914 DOI: 10.1111/mpp.12021] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Alternaria species produce and excrete dimethyl coprogen siderophores to acquire iron. The Alternaria alternata gene AaNPS6, encoding a polypeptide analogous to fungal nonribosomal peptide synthetases, was found to be required for the production of siderophores and virulence on citrus. Siderophores purified from culture filtrates of the wild-type strain did not induce any phytotoxicity on the leaves of citrus. Fungal strains lacking AaNPS6 produced little or no detectable extracellular siderophores and displayed an increased sensitivity to H₂O₂, superoxide-generating compounds (KO₂ and menadione) and iron depletion. Δnps6 mutants were also defective for the production of melanin and conidia. The introduction of a wild-type AaNPS6 under the control of its endogenous promoter to a Δnps6 null mutant at least partially restored siderophore production and virulence to citrus, demonstrating a functional link between iron uptake and fungal pathogenesis. Elevated sensitivity to H₂O₂, seen for the Δnps6 null strain could be relieved by exogenous application of ferric iron. The expression of the AaNPS6 gene was highly up-regulated under low-iron conditions and apparently controlled by the redox-responsive yeast transcriptional regulator YAP1. Hence, the maintenance of iron homeostasis via siderophore-mediated iron uptake also plays an important role in resistance to toxic reactive oxygen species (ROS). Our results demonstrate further the critical role of ROS detoxification for the pathogenicity of A. alternata in citrus.
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Lin WY, Shih YF, Lin CH, Lee CC, Yu YH. The preparation of multi-walled carbon nanotube/poly(lactic acid) composites with excellent conductivity. J Taiwan Inst Chem Eng 2013. [DOI: 10.1016/j.jtice.2012.12.012] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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89
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Lin CH, Kabrawala S, Fox EP, Nobile CJ, Johnson AD, Bennett RJ. Genetic control of conventional and pheromone-stimulated biofilm formation in Candida albicans. PLoS Pathog 2013; 9:e1003305. [PMID: 23637598 PMCID: PMC3630098 DOI: 10.1371/journal.ppat.1003305] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2013] [Accepted: 03/01/2013] [Indexed: 12/13/2022] Open
Abstract
Candida albicans can stochastically switch between two phenotypes, white and opaque. Opaque cells are the sexually competent form of C. albicans and therefore undergo efficient polarized growth and mating in the presence of pheromone. In contrast, white cells cannot mate, but are induced – under a specialized set of conditions – to form biofilms in response to pheromone. In this work, we compare the genetic regulation of such “pheromone-stimulated” biofilms with that of “conventional” C. albicans biofilms. In particular, we examined a network of six transcriptional regulators (Bcr1, Brg1, Efg1, Tec1, Ndt80, and Rob1) that mediate conventional biofilm formation for their potential roles in pheromone-stimulated biofilm formation. We show that four of the six transcription factors (Bcr1, Brg1, Rob1, and Tec1) promote formation of both conventional and pheromone-stimulated biofilms, indicating they play general roles in cell cohesion and biofilm development. In addition, we identify the master transcriptional regulator of pheromone-stimulated biofilms as C. albicans Cph1, ortholog of Saccharomyces cerevisiae Ste12. Cph1 regulates mating in C. albicans opaque cells, and here we show that Cph1 is also essential for pheromone-stimulated biofilm formation in white cells. In contrast, Cph1 is dispensable for the formation of conventional biofilms. The regulation of pheromone- stimulated biofilm formation was further investigated by transcriptional profiling and genetic analyses. These studies identified 196 genes that are induced by pheromone signaling during biofilm formation. One of these genes, HGC1, is shown to be required for both conventional and pheromone-stimulated biofilm formation. Taken together, these observations compare and contrast the regulation of conventional and pheromone-stimulated biofilm formation in C. albicans, and demonstrate that Cph1 is required for the latter, but not the former. Candida albicans is the predominant fungal pathogen afflicting humans, where many infections arise due to its proclivity to form biofilms. Biofilms are complex multicellular communities in which cells exhibit distinct properties to those grown in suspension. They are particularly relevant in the development of device-associated infections, and thus understanding biofilm regulation and biofilm architecture is a priority. C. albicans has the ability to form different types of biofilms under different environmental conditions. Here, we compare the regulation of biofilm formation in conventional biofilms, for which a core transcriptional network has recently been identified, with pheromone-stimulated biofilms, which occur when C. albicans white cells are exposed to pheromone. Our studies show that several regulatory components control biofilm formation under both conditions, including the network transcriptional regulators Bcr1, Brg1, Rob1, and Tec1. However, other transcriptional regulators are specific to each model of biofilm development. In particular, we demonstrate that Cph1, the master regulator of the pheromone response during mating, is essential for pheromone-stimulated biofilm formation but is dispensable for conventional biofilms. These studies provide an in-depth analysis of the regulation of pheromone-stimulated biofilms, and demonstrate that both shared and unique components operate in different models of biofilm formation in this human pathogen.
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Lin CJ, Wu TH, Lin CH, Hung SC, Chiu CF, Liu MJ, Teng MMH, Chang FC, Guo WY, Chang CY. Can iterative reconstruction improve imaging quality for lower radiation CT perfusion? Initial experience. AJNR Am J Neuroradiol 2013; 34:1516-21. [PMID: 23578678 DOI: 10.3174/ajnr.a3436] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Initial results using IR for CT of the head showed satisfactory subjective and objective imaging quality with a 20-40% radiation dose reduction. The aim of our study was to compare the influence of IR and FBP algorithms on perfusion parameters at standard and lowered doses of CTP. MATERIALS AND METHODS Forty patients with unilateral carotid stenosis post-carotid stent placement referred for follow-up CTP were divided into 2 groups (tube currents were 100 mAs in group A and 80 mAs in group B). Datasets were reconstructed with IR and FBP algorithms; and SNRs of gray matter, white matter, and arterial and venous ROIs were compared. CBF, CBV, and MTT means and SNRs were evaluated by using linear regression, and qualitative imaging scores were compared across the 2 algorithms. RESULTS The mean effective radiation dose of group B (2.06 mSv) was approximately 20% lower than that of group A (2.56 mSv). SNRs for ROIs in the dynamic contrast-enhanced images were significantly higher than those for the FBP images. Correlations of the SNRs for CBF, CBV, and MTT across the 2 algorithms were moderate (R² = 0.46, 0.23, and 0.44, respectively). ROIs in gray matter rather than the IR algorithm predicted increasing SNRs in all CBF, CBV, and MTT maps. Two cases of significant restenosis were confirmed in both algorithms. CBV, CBF, and MTT imaging scores did not differ significantly across algorithms or groups. CONCLUSIONS Lower dose CTP (20% below normal dose) without IR can effectively identify oligemic tissue in poststenting follow-up. IR does not alter the absolute values or increase the SNRs of perfusion parameters. Other methods should be attempted to improve SNRs in settings with low tube currents.
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Aguilar M, Alberti G, Alpat B, Alvino A, Ambrosi G, Andeen K, Anderhub H, Arruda L, Azzarello P, Bachlechner A, Barao F, Baret B, Barrau A, Barrin L, Bartoloni A, Basara L, Basili A, Batalha L, Bates J, Battiston R, Bazo J, Becker R, Becker U, Behlmann M, Beischer B, Berdugo J, Berges P, Bertucci B, Bigongiari G, Biland A, Bindi V, Bizzaglia S, Boella G, de Boer W, Bollweg K, Bolmont J, Borgia B, Borsini S, Boschini MJ, Boudoul G, Bourquin M, Brun P, Buénerd M, Burger J, Burger W, Cadoux F, Cai XD, Capell M, Casadei D, Casaus J, Cascioli V, Castellini G, Cernuda I, Cervelli F, Chae MJ, Chang YH, Chen AI, Chen CR, Chen H, Cheng GM, Chen HS, Cheng L, Chernoplyiokov N, Chikanian A, Choumilov E, Choutko V, Chung CH, Clark C, Clavero R, Coignet G, Commichau V, Consolandi C, Contin A, Corti C, Costado Dios MT, Coste B, Crespo D, Cui Z, Dai M, Delgado C, Della Torre S, Demirkoz B, Dennett P, Derome L, Di Falco S, Diao XH, Diago A, Djambazov L, Díaz C, von Doetinchem P, Du WJ, Dubois JM, Duperay R, Duranti M, D'Urso D, Egorov A, Eline A, Eppling FJ, Eronen T, van Es J, Esser H, Falvard A, Fiandrini E, Fiasson A, Finch E, Fisher P, Flood K, Foglio R, Fohey M, Fopp S, Fouque N, Galaktionov Y, Gallilee M, Gallin-Martel L, Gallucci G, García B, García J, García-López R, García-Tabares L, Gargiulo C, Gast H, Gebauer I, Gentile S, Gervasi M, Gillard W, Giovacchini F, Girard L, Goglov P, Gong J, Goy-Henningsen C, Grandi D, Graziani M, Grechko A, Gross A, Guerri I, de la Guía C, Guo KH, Habiby M, Haino S, Hauler F, He ZH, Heil M, Heilig J, Hermel R, Hofer H, Huang ZC, Hungerford W, Incagli M, Ionica M, Jacholkowska A, Jang WY, Jinchi H, Jongmanns M, Journet L, Jungermann L, Karpinski W, Kim GN, Kim KS, Kirn T, Kossakowski R, Koulemzine A, Kounina O, Kounine A, Koutsenko V, Krafczyk MS, Laudi E, Laurenti G, Lauritzen C, Lebedev A, Lee MW, Lee SC, Leluc C, León Vargas H, Lepareur V, Li JQ, Li Q, Li TX, Li W, Li ZH, Lipari P, Lin CH, Liu D, Liu H, Lomtadze T, Lu YS, Lucidi S, Lübelsmeyer K, Luo JZ, Lustermann W, Lv S, Madsen J, Majka R, Malinin A, Mañá C, Marín J, Martin T, Martínez G, Masciocchi F, Masi N, Maurin D, McInturff A, McIntyre P, Menchaca-Rocha A, Meng Q, Menichelli M, Mereu I, Millinger M, Mo DC, Molina M, Mott P, Mujunen A, Natale S, Nemeth P, Ni JQ, Nikonov N, Nozzoli F, Nunes P, Obermeier A, Oh S, Oliva A, Palmonari F, Palomares C, Paniccia M, Papi A, Park WH, Pauluzzi M, Pauss F, Pauw A, Pedreschi E, Pensotti S, Pereira R, Perrin E, Pessina G, Pierschel G, Pilo F, Piluso A, Pizzolotto C, Plyaskin V, Pochon J, Pohl M, Poireau V, Porter S, Pouxe J, Putze A, Quadrani L, Qi XN, Rancoita PG, Rapin D, Ren ZL, Ricol JS, Riihonen E, Rodríguez I, Roeser U, Rosier-Lees S, Rossi L, Rozhkov A, Rozza D, Sabellek A, Sagdeev R, Sandweiss J, Santos B, Saouter P, Sarchioni M, Schael S, Schinzel D, Schmanau M, Schwering G, Schulz von Dratzig A, Scolieri G, Seo ES, Shan BS, Shi JY, Shi YM, Siedenburg T, Siedling R, Son D, Spada F, Spinella F, Steuer M, Stiff K, Sun W, Sun WH, Sun XH, Tacconi M, Tang CP, Tang XW, Tang ZC, Tao L, Tassan-Viol J, Ting SCC, Ting SM, Titus C, Tomassetti N, Toral F, Torsti J, Tsai JR, Tutt JC, Ulbricht J, Urban T, Vagelli V, Valente E, Vannini C, Valtonen E, Vargas Trevino M, Vaurynovich S, Vecchi M, Vergain M, Verlaat B, Vescovi C, Vialle JP, Viertel G, Volpini G, Wang D, Wang NH, Wang QL, Wang RS, Wang X, Wang ZX, Wallraff W, Weng ZL, Willenbrock M, Wlochal M, Wu H, Wu KY, Wu ZS, Xiao WJ, Xie S, Xiong RQ, Xin GM, Xu NS, Xu W, Yan Q, Yang J, Yang M, Ye QH, Yi H, Yu YJ, Yu ZQ, Zeissler S, Zhang JG, Zhang Z, Zhang MM, Zheng ZM, Zhuang HL, Zhukov V, Zichichi A, Zuccon P, Zurbach C. First result from the Alpha Magnetic Spectrometer on the International Space Station: precision measurement of the positron fraction in primary cosmic rays of 0.5-350 GeV. PHYSICAL REVIEW LETTERS 2013; 110:141102. [PMID: 25166975 DOI: 10.1103/physrevlett.110.141102] [Citation(s) in RCA: 123] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Indexed: 06/03/2023]
Abstract
A precision measurement by the Alpha Magnetic Spectrometer on the International Space Station of the positron fraction in primary cosmic rays in the energy range from 0.5 to 350 GeV based on 6.8 × 10(6) positron and electron events is presented. The very accurate data show that the positron fraction is steadily increasing from 10 to ∼ 250 GeV, but, from 20 to 250 GeV, the slope decreases by an order of magnitude. The positron fraction spectrum shows no fine structure, and the positron to electron ratio shows no observable anisotropy. Together, these features show the existence of new physical phenomena.
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Liu CS, Kuo MCT, Su CY, Chen YC, Cheng WC, Chou CY, Liang KF, Han YL, Lin CH. A bacteria injection scheme for in situ bioaugmentation. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2013; 48:1079-1085. [PMID: 23573928 DOI: 10.1080/10934529.2013.774601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
This article presents an innovative design for inoculating the desired organisms to stratified geological layers at desired rates during in-situ bioaugmentation. The new delivery system consists of intermittent porous tubes connected in series with impermeable polyethylene tubes that run horizontally in each stratified layer of a contaminated aquifer. A bioaugmentation test using the new delivery system was conducted to inject an enriched culture of Escherichia coli (E. coli). Results of the test indicated that the distribution of E. coli through each porous tube was fairly uniform. A mathematical model previously developed to calculate the distribution of water flow through each porous tube was modified to calculate the distribution of E. coli. Geological layers often have different hydraulic conductivities. By controlling the permeability and the length of porous tubes placed in stratified layers, the new design provides a means to selectively deliver aqueous bacteria to various layers at desired rates according to aquifer heterogeneity.
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Liao YF, Chang CC, Wang DP, Tseng BH, Liao YD, Lin CH. A novel approach for normalizing the photoreflectance spectrum by using polymer-dispersed liquid crystal. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2012; 83:103904. [PMID: 23126779 DOI: 10.1063/1.4757399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
This study developed a novel type of normalization procedure for modulation reflectance spectroscopy experiments to obtain the relative change in the reflectance spectrum, ΔR/R. This technique uses a polymer-dispersed liquid crystal to ensure that the dc component of the signal from the detector remained constant by varying the intensity of the light striking the sample. This method is particularly useful for photoreflectance measurement, which may encounter background problems because of scattered pump light and/or photoluminescence. It does not require a change in the gain of the detector or the use of a variable neutral density filter mounted on a servo-motor.
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Lin TH, Lin CH, Shih JC, Su YN, Wu ET, Lee CN. Effect of arterioarterial anastomosis on early-onset umbilical artery flow abnormality in a monochorionic-diamniotic twin. ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2012; 40:371-372. [PMID: 22302609 DOI: 10.1002/uog.11111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
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Chen LH, Lin CH, Chung KR. Roles for SKN7 response regulator in stress resistance, conidiation and virulence in the citrus pathogen Alternaria alternata. Fungal Genet Biol 2012; 49:802-13. [PMID: 22902811 DOI: 10.1016/j.fgb.2012.07.006] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Revised: 07/17/2012] [Accepted: 07/26/2012] [Indexed: 01/17/2023]
Abstract
"Two-component" histidine kinase (HSK1) is the primary regulator of resistance to sugar osmotic stress and sensitivity to dicarboximide or phenylpyrrole fungicides in the citrus fungal pathogen Alternaria alternata. On the other hand, the mitogen-activated protein kinase HOG1 confers resistance solely to salts and oxidative stress. We report here independent and shared functions of the SKN7-mediated signaling pathway with HSK1 and HOG1. SKN7, a putative transcription downstream regulator of HSK1, is primarily required for cellular resistance to oxidative and sugar-induced osmotic stress. SKN7, perhaps acting in parallel with HOG1, is required for resistance to H(2)O(2), tert-butyl hydroperoxide, and cumyl peroxide, but not to the superoxide-generating compounds - menadione, potassium superoxide, and diamide. Because of phenotypic commonalities, SKN7 is likely involved in resistance to sugar-induced osmotic stress via the HSK1 signaling pathway. However, mutants lacking SKN7 displayed wild-type sensitivity to NaCl and KCl salts. SKN7 is constitutively localized in the nucleus regardless of H(2)O(2) treatment. When compared to the wild type, skn7 mutants exhibited lower catalase, peroxidase, and superoxide dismutase activities and induced significantly fewer necrotic lesions on the susceptible citrus cultivar. The skn7 mutant exhibited fungicide resistance at levels between the hsk1 and the hog1 mutant strains. Skn7/hog1 double mutants exhibited fungicide resistance, similar to the strain with a single AaHSK1 gene mutation. Moreover, the A. alternata SKN7 plays a role in conidia formation. Conidia produced by the skn7 mutant are smaller and have fewer transverse septae than those produced by wild type. All altered phenotypes in the mutant were restored by introducing and expressing a wild-type copy of SKN7 under control of the endogenous promoter.
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Liu TY, Chen Y, Wang HH, Huang YL, Chao YC, Tsai KT, Cheng WC, Chuang CY, Tsai YH, Huang CY, Wang DW, Lin CH, Wang JK, Wang YL. Differentiation of bacteria cell wall using Raman scattering enhanced by nanoparticle array. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2012; 12:5004-8. [PMID: 22905567 DOI: 10.1166/jnn.2012.4941] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We have fabricated surface-enhanced Raman scattering (SERS) substrates based on arrays of silver nanoparticles grown on porous anodic alumina templates. Using this nanotechnology platform, label-free and high-speed detection of bacteria are achieved. SERS spectra of various bacteria including Staphylococcus Aureus (Gram-positive bacterium), Klebsiella Pneumoniae (Gram-negative bacterium), and Mycobacterium Smegmatis (Mycobacterium) were recorded. The highly reproducible SERS-based technological platform is capable of differentiating different kinds of bacteria by PCA, LDA, clustering analysis, and SVM methods, which provides promising opportunity for biosensing of clinical microbes.
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Lin CW, Tseng SW, Yang SF, Ko CP, Lin CH, Wei LH, Chien MH, Hsieh YS. Role of lipocalin 2 and its complex with matrix metalloproteinase-9 in oral cancer. Oral Dis 2012; 18:734-40. [PMID: 22533572 DOI: 10.1111/j.1601-0825.2012.01938.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVES Recent evidence demonstrated that lipocalin (LCN)2 is induced in many types of human cancer, while the detection of its complex with matrix metalloproteinase (MMP)-9 is correlated with the cancer disease status. We attempted to evaluate plasma expressions of LCN2, MMP-9, and their complex (LCN2/MMP-9) during the diagnostic work-up of patients with oral squamous cell carcinoma (OSCC) and investigated their correlations with disease progression. METHODS In total, 195 patients with OSCC and 81 healthy controls were recruited. Expression levels of LCN2, MMP-9, and LCN2/MMP-9 were determined with immunoenzymatic assays. RESULTS Patients with OSCC exhibited significantly higher levels of LCN2, MMP-9, and LCN2/MMP-9 compared with healthy controls (LCN2: P < 0.001; MMP-9: P < 0.001; LCN2/MMP-9: P < 0.01). Plasma levels of LCN2, MMP-9, and LCN2/MMP-9 in patients with OSCC were significantly correlated with each other and were associated with more-advanced clinical stages (P < 0.05) and/or a larger tumor size (P < 0.05), but were not associated with positive lymph-node metastasis or distal metastasis. CONCLUSION Our results suggest that plasma levels of LCN2 and the LCN2/MMP-9 complex may be useful in non-invasively monitoring OSCC progression, while supporting their potential role as biomarkers of oral cancer disease status.
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Lin CH, Kuo MCT, Su CY, Liang KF, Han YL. A nutrient injection scheme for in situ bio-remediation. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2012; 47:280-288. [PMID: 22242881 DOI: 10.1080/10934529.2012.640907] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Geological layers often have different hydraulic conductivities. This paper presents an innovative design for delivering aqueous substrates and nutrients to various stratified layers at desired rates during in-situ bio-stimulation. The new delivery system consists of intermittent porous tubes connected in series with impermeable polyethylene tubes that run horizontally in each stratified layer of a contaminated aquifer. Results of the tracer test indicated that the distribution of tritium through each porous tube was fairly uniform. A mathematical model was also developed to calculate the distribution of water flow through each porous tube. By controlling the permeability and the length of porous tubes placed in stratified layers, the new design provides a means to selectively deliver nutrients to various layers at desired rates according to aquifer heterogeneity.
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Lin CH, Lee YY, Liu CC, Chen HF, Ko MC, Li CY. Urbanization and prevalence of depression in diabetes. Public Health 2011; 126:104-11. [PMID: 22178148 DOI: 10.1016/j.puhe.2011.10.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2010] [Revised: 06/13/2011] [Accepted: 10/27/2011] [Indexed: 11/18/2022]
Abstract
OBJECTIVES To depict recent secular trend (2001-2005) in prevalence of depression among diabetic population in Taiwan, and to explore the influences of urbanization on the prevalence of depression. STUDY DESIGN A descriptive correlation study design relating urbanization and prevalence of depression. METHODS Annual prevalence of depression was calculated as the ratio of number of individuals with depression (ICD-9-CM: 296, 309, or 311) to the size of diabetic population (ICD-9-CM: 250), which were ascertained from ambulatory care claim data of Taiwan's National Health Insurance between 2001 and 2005. Multivariate Poisson regression analysis was used to assess the secular trend in the prevalence of comorbid depression, and to appraise the influence of urbanization on prevalence of depression in diabetic patients. RESULTS The prevalence of depression among diabetic population increased annually from 22.6/10(3) in 2001 to 27.0/10(3) in 2005 with a significantly and linearly rising trend (β = 0.0461, p < 0.0001). Diabetic population living in urban areas showed the largest increase in prevalence (6.3/10(3)), followed by those from rural areas (5.6/10(3)). Compared to the diabetic patients residing in rural areas, those living in urban areas (RR = 1.28, 95% CI = 1.25-1.31) and those from satellite towns (RR = 1.22, 95% CI = 1.19-1.25) both had significantly increased adjusted RR. CONCLUSIONS There is a significant increasing trend in prevalence of depression among diabetic population in recent years in Taiwan. Diabetic patients from urban areas not only had the greatest prevalence of depression but also showed the largest increase in prevalence during the study period, which highlights a need for managing depression in urban diabetes.
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Lin CH, Choi A, Bennett RJ. Defining pheromone-receptor signaling in Candida albicans and related asexual Candida species. Mol Biol Cell 2011; 22:4918-30. [PMID: 21998194 PMCID: PMC3237633 DOI: 10.1091/mbc.e11-09-0749] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The pheromone response in Candida albicans is mediated by the Ste2 receptor. Intracellular (IC) loop 3 and C-terminal tail regions of Ste2 are required for signaling, whereas the large IC1 region is dispensable. Heterologous expression of receptors from asexual species can also drive signaling in C. albicans, allowing functional pheromone-receptor couples to be analyzed. Candida albicans is an important human fungal pathogen in which sexual reproduction is under the control of the novel white–opaque switch. Opaque cells are the mating-competent form, whereas white cells do not mate but can still respond to pheromones, resulting in biofilm formation. In this study, we first define the domains of the α-pheromone receptor Ste2 that are necessary for signaling in both white and opaque forms. Both cell states require the IC loop 3 (IC3) and the C-terminal tail of Ste2 for the cellular response, whereas the first IC loop (IC1) of Ste2 is dispensable for signaling. To also address pheromone-receptor interactions in related species, including apparently asexual Candida species, Ste2 orthologues were heterologously expressed in Candida albicans. Ste2 receptors from multiple Candida clade species were functional when expressed in C. albicans, whereas the Ste2 receptor of Candida lusitaniae was nonfunctional. Significantly, however, expression of a chimeric C. lusitaniae Ste2 receptor containing the C-terminal tail of Ste2 from C. albicans generated a productive response to C. lusitaniae pheromone. This system has allowed us to characterize pheromones from multiple Candida species and indicates that functional pheromone-receptor couples exist in fungal species that have yet to be shown to undergo sexual mating.
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