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Ahn K, Oh J, Park K, Kim M, Jin S, Kim J, Lee J, Choi S, Seong I, Jeong J. PP.06.23. J Hypertens 2015. [DOI: 10.1097/01.hjh.0000467897.73588.01] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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177
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Zhao Y, Anderson NC, Zhu K, Aguiar JA, Seabold JA, van de Lagemaat J, Branz HM, Neale NR, Oh J. Oxidatively stable nanoporous silicon photocathodes with enhanced onset voltage for photoelectrochemical proton reduction. NANO LETTERS 2015; 15:2517-2525. [PMID: 25723908 DOI: 10.1021/acs.nanolett.5b00086] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Stable and high-performance nanoporous "black silicon" photoelectrodes with electrolessly deposited Pt nanoparticle (NP) catalysts are made with two metal-assisted etching steps. Doubly etched samples exhibit an ∼300 mV positive shift in photocurrent onset for photoelectrochemical proton reduction compared to oxide-free planar Si with identical catalysts. We find that the photocurrent onset voltage of black Si photocathodes prepared from single-crystal planar Si wafers by an Ag-assisted etching process increases in oxidative environments (e.g., aqueous electrolyte) owing to a positive flat-band potential shift caused by surface oxidation. However, within 24 h, the surface oxide layer becomes a kinetic barrier to interfacial charge transfer that inhibits proton reduction. To mitigate this issue, we developed a novel second Pt-assisted etch process that buries the Pt NPs deep into the nanoporous Si surface. This second etch shifts the onset voltage positively, from +0.25 V to +0.4 V versus reversible hydrogen electrode, and reduces the charge-transfer resistance with no performance decrease seen for at least two months. PEC performance was stable owing to Pt NP catalysts that were buried deeply in the photoelectrode by the second etch, below a thick surface layer comprised primarily of amorphous SiO2 along with some degree of remaining crystalline Si as observed by scanning and transmission electron micrographs. Electrochemical impedance studies reveal that the second etch leads to a considerably smaller interfacial charge-transfer resistance than samples without the additional etch, suggesting that burying the Pt NPs improves the interfacial contact to the crystalline silicon surface.
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Oh J, Kerns S, Ostrer H, Rosenstein B, Deasy J. OC-0082: A machine learning method demonstrates that a large number of SNPs contribute to clinical radiosensitivity. Radiother Oncol 2015. [DOI: 10.1016/s0167-8140(15)40082-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Oh J, Barve M, Grosen E, Fine B, Heffernan T, Matthews C, Stringer C, Koon E, Goodman H, Fleming E, DeMars L, Bergman M, Senzer N, Nemunaitis J. Randomized phase II trial of maintenance autologous tumor cell vaccine (FANG™) following clinical complete response (cCR) in stage III/IV ovarian cancer: Preliminary results. Gynecol Oncol 2015. [DOI: 10.1016/j.ygyno.2015.01.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Karasik M, Weaver JL, Aglitskiy Y, Oh J, Obenschain SP. Suppression of laser nonuniformity imprinting using a thin high-z coating. PHYSICAL REVIEW LETTERS 2015; 114:085001. [PMID: 25768766 DOI: 10.1103/physrevlett.114.085001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Indexed: 06/04/2023]
Abstract
Imprinting of laser nonuniformity is a limiting factor in direct-drive inertial confinement fusion experiments, particularly when available laser smoothing is limited. A thin (∼400 Å) high-Z metal coating is found to substantially suppress laser imprint for planar targets driven by pulse shapes and intensities relevant to implosions on the National Ignition Facility while retaining low adiabat target acceleration. A hybrid of indirect and direct drive, this configuration results in initial ablation by x rays from the heated high-Z layer, creating a large standoff for perturbation smoothing.
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Giallongo F, Hristov AN, Oh J, Frederick T, Weeks H, Werner J, Lapierre H, Patton RA, Gehman A, Parys C. Effects of slow-release urea and rumen-protected methionine and histidine on performance of dairy cows. J Dairy Sci 2015; 98:3292-308. [PMID: 25726096 DOI: 10.3168/jds.2014-8791] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Accepted: 01/10/2015] [Indexed: 11/19/2022]
Abstract
This experiment was conducted with the objective to investigate the effects of slow-release urea and rumen-protected (RP) Met and His supplementation of a metabolizable protein (MP)-deficient diet (according to NRC, 2001) on lactation performance of dairy cows. Sixty lactating Holstein cows were used in a 10-wk randomized complete block-design trial. Cows were fed a covariate diet for 2 wk and then assigned to one of the following treatments for an 8-wk experimental period: (1) MP-adequate diet [AMP; 107% of MP requirements, based on the National Research Council (NRC, 2001)]; (2) MP-deficient diet (DMP; 95% of MP requirements); (3) DMP supplemented with slow-release urea (DMPU); (4) DMPU supplemented with RPMet (DMPUM); and (5) DMPUM supplemented with RPHis (DMPUMH). Total-tract apparent digestibility of dry matter, organic matter, neutral detergent fiber, and crude protein, and urinary N and urea-N excretions were decreased by DMP, compared with AMP. Addition of slow-release urea to the DMP diet increased urinary urea-N excretion. Dry matter intake (DMI) and milk yield (on average 44.0±0.9kg/d) were not affected by treatments, except DMPUMH increased DMI and numerically increased milk yield, compared with DMPUM. Milk true protein concentration and yield were increased and milk fat concentration tended to be decreased by DMPUMH, compared with DMPUM. Cows gained less body weight on the DMP diet, compared with AMP. Plasma concentrations of His and Lys were not affected by treatments, whereas supplementation of RPMet increased plasma Met concentration. Plasma concentration of 3-methylhistidine was or tended to be higher for DMP compared with AMP and DMPU, respectively. Addition of RPHis to the DMPUM diet tended to increase plasma glucose and creatinine. In conclusion, feeding a 5% MP-deficient diet (according to NRC, 2001) did not decrease DMI and yields of milk and milk components, despite a reduction in nutrient digestibility. Supplementation of RPHis increased DMI and milk protein concentration and yield. These results are in line with our previous data and suggest that His may have a positive effect on voluntary feed intake and milk production and composition in high-yielding dairy cows fed MP-deficient diets.
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Oh J, Ji SC, Lee H, Yu KS, Jang IJ. Response to "Induction of both P-glycoprotein and specific cytochrome P450 by aspirin eventually does not alter the antithrombotic effect of clopidogrel". Clin Pharmacol Ther 2015; 97:325. [PMID: 25669937 DOI: 10.1002/cpt.74] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Lee C, Oh J, Hristov A, Harvatine K, Vazquez-Anon M, Zanton G. Effect of 2-hydroxy-4-methylthio-butanoic acid on ruminal fermentation, bacterial distribution, digestibility, and performance of lactating dairy cows. J Dairy Sci 2015; 98:1234-47. [DOI: 10.3168/jds.2014-8904] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2014] [Accepted: 10/26/2014] [Indexed: 12/15/2022]
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Park SJ, Oh J, Kim YK, Park JH, Park JY, Hong HK, Park KH, Lee JE, Kim HM, Chung JY, Woo SJ. Intraocular pharmacokinetics of intravitreal vascular endothelial growth factor-Trap in a rabbit model. Eye (Lond) 2015; 29:561-8. [PMID: 25592118 DOI: 10.1038/eye.2014.329] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Accepted: 12/07/2014] [Indexed: 12/22/2022] Open
Abstract
PURPOSE To determine intraocular pharmacokinetic properties of intravitreally injected vascular endothelial growth factor (VEGF)-Trap in a rabbit model. METHODS VEGF-Trap was intravitreally injected in 18 rabbit eyes. Eyes were enucleated 1 h and 1, 2, 5, 14, and 30 days after injections and immediately frozen at -80 °C. Concentration of VEGF-Trap in vitreous, aqueous humor, and retina/choroid was determined using an indirect enzyme-linked immunosorbent assay and analyzed to obtain pharmacokinetic properties. RESULTS Maximum concentration of VEGF-Trap was achieved at 1 h in all three tissues. A one-compartment model of distribution was selected as the final model for all tissues studied. Estimated half-life of VEGF-Trap in vitreous, aqueous humor, and retinal/choroid was 87.1, 36.8, and 35.0 h, respectively, and estimated mean residence time was 125.7, 53.1, and 50.5 h, respectively. Area under the curve from time 0 to the end point was 10009.8, 3945.1, and 1189.3, respectively. Total exposure of the aqueous humor and retina/choroid to VEGF-Trap was 39.4% and 11.9% of vitreous exposure, respectively. CONCLUSION The vitreous half-life of VEGF-Trap is 3.63 days. This is shorter than that of bevacizumab (6.99 days) and longer than that of ranibizumab (2.51 days), as shown in studies using the same experimental settings. The concentration of VEGF-Trap peaked at 1 h after injections in all eye tissues studied.
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Ciampi Q, Bombardini T, Cortigiani L, Pratali L, Rigo F, Villari B, Picano E, Sicari R, Teramoto K, Suzuki K, Satoh Y, Minami K, Mizukoshi K, Kamijima R, Kou S, Takai M, Izumo M, Akashi Y, Cifra B, Dragulescu A, Friedberg M, Mertens L, O'driscoll J, Gargallo-Fernandez P, Araco M, Perez-Lopez M, Sharma R, Abram S, Arruda-Olson M, Scott G, Pellikka A, Nkomo T, Oh J, Milan A, Mccully B, Aguiar Rosa S, Portugal G, Moura Branco L, Galrinho A, Afonso Nogueira M, Abreu J, Cacela D, Abreu A, Fragata J, Cruz Ferreira R, Mielczarek A, Kasprzak J, Chrzanowski L, Plewka M, Lipiec P, Qawoq D, Rechcinski T, Wierzbowska-Drabik K, Magne J, Donal E, Dulgheru R, Pierard L, Lancellotti P. Oral Abstract session: Stress echo in clinical practice: Friday 5 December 2014, 08:30-10:00 * Location: Agora. Eur Heart J Cardiovasc Imaging 2014. [DOI: 10.1093/ehjci/jeu251] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Magne J, Pierard L, Lancellotti P, Marc Dweck M, Jenkins W, Shah A, Vesey A, Pringle M, Chin C, Pawade T, Boon N, Rudd J, Newby D, Boulogne C, Mohty D, Magne J, Varroud-Vial N, Ettaif H, Lavergne D, Damy T, Aboyans V, Bridoux F, Jaccard A, Abram S, Arruda-Olson M, Scott G, Pellikka A, Nkomo T, Oh J, Milan A, Mccully B. Roelandt's Young Investigator Award session: Thursday 4 December 2014, 15:30-16:30 * Location: Agora. Eur Heart J Cardiovasc Imaging 2014. [DOI: 10.1093/ehjci/jeu249] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Lim H, Kim D, Kim T, Kim S, Baek J, Chang H, Park J, Oh J. Is Elective Inguinal Radiation Therapy Necessary for Locally Advanced Rectal Cancer Involving Anal Canal? Int J Radiat Oncol Biol Phys 2014. [DOI: 10.1016/j.ijrobp.2014.05.1249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Ohta T, Oh J, Mittelbronn M, Paulus W, Ohgaki H. P07.04 * PROMOTER METHYLATION OF THE LATS1 AND LATS2 GENES IN SCHWANNOMAS. Neuro Oncol 2014. [DOI: 10.1093/neuonc/nou174.186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Thor M, Olsson C, Oh J, Petersen S, Alsadius D, Høyer M, Pettersson N, Bentzen L, Deasy J, Muren L, Steineck G. Identifying Groups of Patient-Reported Gastro-Intestinal Symptoms Using Factor Analysis. Int J Radiat Oncol Biol Phys 2014. [DOI: 10.1016/j.ijrobp.2014.05.2446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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190
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Kim S, Lee S, Oh J. P13.16 * COMPLICATIONS AFTER GAMMA KNIFE RADIOSURGERY FOR BRAIN TUMORS LOCATING ADJACENT THE BRAINSTEM. Neuro Oncol 2014. [DOI: 10.1093/neuonc/nou174.262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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191
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Chung HW, Yun CM, Kim JT, Kim SW, Oh J, Huh K. Retinal sensitivity assessed by microperimetry and corresponding retinal structure and thickness in resolved central serous chorioretinopathy. Eye (Lond) 2014; 28:1223-30. [PMID: 25081286 DOI: 10.1038/eye.2014.185] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2013] [Accepted: 06/26/2014] [Indexed: 01/08/2023] Open
Abstract
PURPOSE To investigate the relationship between retinal sensitivity (RS) assessed by microperimetry (MP) and retinal structural changes in patients with resolved central serous chorioretinopathy (CSC). METHODS Spectral domain optical coherence tomography (OCT) examination and MP tests were performed in patients with resolved CSC. Point-to-point correlation was performed between RS and corresponding retinal structural changes using Pearson's correlation analysis. In addition, in a 1-mm zone in the central fovea, a correlation was calculated between the mean RS and the mean central retinal thickness (CRT). RESULTS Eighty-four eyes were analyzed. The total number of MP test points was 1092 (84 eyes × 13 points). The mean RS and retinal point thickness (RPT) of all test points were 13.53±3.84 dB and 208.6±48.0 μm, respectively. The RS and RPT were significantly decreased in the test points with loss of the ellipsoid portion of the inner segments (EPIS) (P<0.0001). Within the 1-mm foveal center zone, there was a significant correlation between mean RS and mean CRT (r=0.432, P<0.0001) and between RS and the corresponding RPT (r=0.339, P<0.0001). CONCLUSION RS was dependent on the status of the EPIS in patients with resolved CSC. The correlation between mean RS and mean CRT was compatible with the point-to-point correlation between RS and the corresponding RPT.
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Oh J, Apte A, Folkerts M, Kohutek Z, Wu A, Rimmer A, Lee N, Deasy J. WE-E-17A-03: FDG-PET-Based Radiomics to Predict Local Control and Survival Following Radiotherapy. Med Phys 2014. [DOI: 10.1118/1.4889445] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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193
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Kim Y, Lee EJ, Hong S, Koo B, Seo W, Oh J, Kim YG, Lee CK, Yoo B. AB0500 B-Cell Depleting Therapy for SLE Related Refractory Thrombocytopenia. Ann Rheum Dis 2014. [DOI: 10.1136/annrheumdis-2014-eular.3221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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194
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Hong S, Lee EJ, Kim Y, Koo B, Chang EJ, Lee EJ, Seo W, Oh J, Kim TH, Kim YG, Lee CK, Yoo B. OP0111 Mechanism of New Bone Formation in Ankylosing Spondylitis: the Role of IL-32 in Osteoblast Differentiation. Ann Rheum Dis 2014. [DOI: 10.1136/annrheumdis-2014-eular.2857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Gay H, Oh J, Apte A, Dyk P, Mullen D, Eschen L, Fergus S, Chin R, Thorstad W, Deasy J. WE-E-BRE-09: Investigation of the Association Between Radiation-Induced Pain and Radiation Dose in Head and Neck Cancer Patients. Med Phys 2014. [DOI: 10.1118/1.4889438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Kim Y, Lee EJ, Hong S, Koo B, Seo W, Oh J, Kim YG, Lee CK, Yoo B. AB0154 Pathogenic Role of Irhom2 in Seropositive Rheumatoid Arthritis. Ann Rheum Dis 2014. [DOI: 10.1136/annrheumdis-2014-eular.3199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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197
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Oh J, Deasy J. WE-D-BRE-05: Prediction of Late Radiation-Induced Proctitis in Prostate Cancer Patients Using Chromosome Aberration and Cell Proliferation Rate. Med Phys 2014. [DOI: 10.1118/1.4889395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Chamney P, Moissl U, Wabel P, Amato C, Stuard S, Menzer M, Vollmeier C, Williams G, Shrivastava R, Chess J, Catling E, Brown C, Baker E, Ashcroft R, Mikhail A, Djukanovic L, Djuric Z, Knezevic V, Lazarevic T, Ljubenovic S, Markovic R, Rabrenovic V, Marinkovic J, Dimkovic N, Lebourg L, Ridel C, De Preneuf H, Le Roy F, Petitclerc T, Wester M, Simonis F, Kooman JP, Boer WH, Gerritsen KGF, Joles JA, Yamamoto KI, Eguchi K, Hirakawa S, Murakami J, Akiba T, Mineshima M, Stamopoulos D, Mpakirtzi N, Lavranos A, Panagiotou M, Barbarousi D, Matsouka C, Grapsa E, Abbas SR, Zhu F, Kaysen GA, Kotanko P, Levin NW, Vasilevsky A, Konoplev G, Stepanova O, Rubinsky A, Zemchenkov A, Gerasimchuk R, Frorip A, Abe T, Yamamoto KI, Ishimori I, Eguchi K, Murakami J, Mineshima M, Akiba T, Kusztal M, Go Biowski, T, Letachowicz K, Koni Ski P, Witkowski G, Pozna Ski P, Weyde W, Klinger M, Ito M, Ito S, Suzuki M, Masakane I, Navarro D, Goncalves C, Ferreira AC, Jorge C, Gil C, Aires I, Matias P, Mendes M, Azevedo A, Gomes F, Ferreira A, Perazzini C, Scutiero L, Brighenti L, Surace A, Steckiph D, Rovatti P, Severi S, Soltysiak J, Warzywoda A, Musielak A, Ostalska-Nowicka D, Zachwieja J, Goeksel T, Garnier H, Ritzerfeld M, Mann H, Babinet F, Allard B, Todorova V, Hamont C, Begri R, Dekker M, Taks M, Konings C, Scharnhorst V, Borawski J, Gozdzikiewicz-Lapinska J, Naumnik B, Lodi CA, Surace A, Grandi E, Rovatti P, Mancini E, Santoro A, Sereni L, Caiazzo M, Corazza L, Atti M, Palladino G, Sakurai K, Saito T, Hosoya H, Yamauchi F, Kurihara T, Tanibayashi Y, Ikebe N, Antonic M, Gubensek J, Drozg A, Vannier E, Mattio E, Todorova V, Ragon A, Brunet P, Klimm W, Pleskacz K, Pietrzak B, Niemczyk S, Leypoldt JK, Bernardo A, Muller M, Marbury TC, Culleton BF, Zeraati AA, Hekmat R, Reyhani HR, Sharifipoor F, Bolasco P, Sitzia I, Monni A, Mereu MC, Pinna AM, Logias F, Ghisu T, Passaghe M, Gazzanelli L, Ganadu M, Piras A, Cossu M, Contu B, Palleschi S, Rossi B, Atti M, Caiazzo M, Sereni L, Palladino G, Ghezzi PM, Kron S, Schneditz D, Leimbach T, Aign S, Kron J, Seker Kockara A, Kayatas M, Huzmeli C, Candan F, Yilmaz MB, Ahmed BA, Bejosano CN, Samra Abouchacra SA, Al Falahi SZ, Abdul Moniem KM, Dastoor H, Kim S, Oh J, Sin Y, Kim J, Lee J. HAEMODIALYSIS TECHNIQUES AND ADEQUACY 2. Nephrol Dial Transplant 2014. [DOI: 10.1093/ndt/gfu173] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Martins MJ, Fischmeister FP, Puig-Waldmüller E, Oh J, Geissler A, Robinson S, Fitch WT, Beisteiner R. Fractal image perception provides novel insights into hierarchical cognition. Neuroimage 2014; 96:300-8. [PMID: 24699014 DOI: 10.1016/j.neuroimage.2014.03.064] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Revised: 03/19/2014] [Accepted: 03/24/2014] [Indexed: 11/19/2022] Open
Abstract
Hierarchical structures play a central role in many aspects of human cognition, prominently including both language and music. In this study we addressed hierarchy in the visual domain, using a novel paradigm based on fractal images. Fractals are self-similar patterns generated by repeating the same simple rule at multiple hierarchical levels. Our hypothesis was that the brain uses different resources for processing hierarchies depending on whether it applies a "fractal" or a "non-fractal" cognitive strategy. We analyzed the neural circuits activated by these complex hierarchical patterns in an event-related fMRI study of 40 healthy subjects. Brain activation was compared across three different tasks: a similarity task, and two hierarchical tasks in which subjects were asked to recognize the repetition of a rule operating transformations either within an existing hierarchical level, or generating new hierarchical levels. Similar hierarchical images were generated by both rules and target images were identical. We found that when processing visual hierarchies, engagement in both hierarchical tasks activated the visual dorsal stream (occipito-parietal cortex, intraparietal sulcus and dorsolateral prefrontal cortex). In addition, the level-generating task specifically activated circuits related to the integration of spatial and categorical information, and with the integration of items in contexts (posterior cingulate cortex, retrosplenial cortex, and medial, ventral and anterior regions of temporal cortex). These findings provide interesting new clues about the cognitive mechanisms involved in the generation of new hierarchical levels as required for fractals.
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Oh J, Shin D, Lim KS, Lee S, Jung KH, Chu K, Hong KS, Shin KH, Cho JY, Yoon SH, Ji SC, Yu KS, Lee H, Jang IJ. Aspirin decreases systemic exposure to clopidogrel through modulation of P-glycoprotein but does not alter its antithrombotic activity. Clin Pharmacol Ther 2014; 95:608-16. [PMID: 24566733 DOI: 10.1038/clpt.2014.49] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2014] [Accepted: 02/18/2014] [Indexed: 11/09/2022]
Abstract
Decreased oral clopidogrel absorption caused by induction of intestinal permeability glycoprotein (P-gp) expression after aspirin administration was observed in rats. This study evaluated the effect of aspirin coadministration on the pharmacokinetics/pharmacodynamics of clopidogrel in humans. A single 75-mg dose of clopidogrel was orally administered before and after 2 and 4 weeks of once-daily 100-mg aspirin administration in 18 healthy volunteers who were recruited based on CYP2C19 and PON1 genotypes. Plasma concentrations of clopidogrel and its active metabolite, H4, and relative platelet inhibition (RPI) were determined. The P-gp microRNA miR-27a increased by up to 7.67-fold (P = 0.004) and the clopidogrel area under the concentration-time curve (AUC) decreased by 14% (P > 0.05), but the AUC of H4 remained unchanged and RPI increased by up to 15% (P = 0.002) after aspirin administration. These findings indicate low-dose aspirin coadministration may decrease clopidogrel bioavailability but does not decrease its efficacy.
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