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Rodionov AV, Nosov NN, Kim ES, Machs EM, Punina EO, Probatova NS. [The origin of polyploid genomes of bluegrasses Poa L. and gene flow between Northern Pacific and sub-Antarctic islands]. GENETIKA 2010; 46:1598-1608. [PMID: 21434413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The involvement of present-day diploid bluegrass species in the formation of polyploid genomes was investigated using comparison of sequences of internal transcribed spacers ITS1 and ITS2, and the 5.8S rDNA sequence. It was demonstrated that highly polyploid New Zealand bluegrasses, P. cita (2n = 84; ca. 96 to 100), P. chathamica (2n = 112), and P. litorosa (2n = 263 to 266) formed separate highly supported clade together with tetraploids (2n = 28) P. intrusa, P. anceps, and P. trioides (Austrofestuca littoralis). Among the diploid species (2n = 14), the closest relatives of these species, as well as of the polyploid species of section Poa, are the genomes of Eurasian species P. remota, P. chaixcii (sect. Homalopoa), P densa (Bolbophorum), and P. sibirica (sect. Macropoa). Nuclear genomes of polyploid Stenopoa, Tichopoa, Oreinos, and Secundae are definitely related to the genome of Arctic species P. pseudabbreviata (sect. Abbreviatae). On the contrary, judging by the genes for nuclear 45S rRNA, genomes of diploid P. trivialis (sect. Pandemos), P. annua, and P. supina (sect. Ochlopoa both) are only remotely related to the genomes of highly polyploid species (distances p between them and other bluegrass species from different sections of subgenus Poa constitute 6-10% and 11-15%, respectively). The conclusion on the relationships between highly polyploid and diploid bluegrass species was tested using analysis of synapomorphic mutations in the 5.8S rRNA gene. It was demonstrated that genomes of Poa eminens (2n = 42) and P. schischkinii (2n = 70) (sect. Arctopoa both) were noticeably different in ITS regions from the genomes of the members of the type subgenus Poa. A comparison of the Arctopoa ITS regions showed that the differences between them constituted only 0.2%. At the same time, p distances between the Arctopoa ITS and those from the species belonging to other sections of the genus Poa varied from 5 to 14%. South American species P chonotica (sect. Andinae) (=Ncoraepoa chonotica) (2n = 42) was found to be related to Arctagrostis, Festucella, and Hookerochloa, being at the same time quite distant from the other species of the genus Poa. Polymorphic in chromosome number highly polyploid species of Northern Hemisphere, P. arctica (2n = 42 to 106), P. turneri (2n = 42, 63 to 64), and P. smirnovii (2n = 42, 70) (sect. Malacanthae) are relative to a large group of tetraploid (2n = 28) endemic bluegrass species from New Zealand and sub-Antarctic islands (P. novae-zelandiae and allied species).
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Kwak YG, Lee SO, Kim HY, Kim YK, Park ES, Jin HY, Choi HJ, Jeong SY, Kim ES, Ki HK, Kim SR, Lee JY, Hong HK, Kim S, Lee YS, Oh HB, Kim JM. Risk factors for device-associated infection related to organisational characteristics of intensive care units: findings from the Korean Nosocomial Infections Surveillance System. J Hosp Infect 2010; 75:195-9. [PMID: 20434798 DOI: 10.1016/j.jhin.2010.01.014] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2009] [Accepted: 01/13/2010] [Indexed: 10/19/2022]
Abstract
Device-associated infections (DAIs) have been the major causes of morbidity and mortality of patients in intensive care units (ICUs). This study evaluated the risk factors for DAIs in ICUs. Ninety-six medical or surgical ICUs of 56 hospitals participated in the Korean Nosocomial Infections Surveillance System between July 2007 and June 2008. The occurrence of catheter-associated urinary tract infection (CAUTI), central line-associated bloodstream infection (CABSI), and ventilator-associated pneumonia (VAP) were monitored and DAI rates were calculated. Data associated with ICU characteristics were collected and Poisson regression was used for statistical analysis. Rates of CAUTI, CABSI, and VAP were 3.87 per 1000 urinary catheter days, 2.23 per 1000 central line days, and 1.89 per 1000 mechanical ventilator days, respectively. Rates of CAUTI were higher in ICUs in Seoul (P=0.032) and ICUs of major teaching hospitals (P=0.010). The ICUs of university-affiliated hospitals showed lower CAUTI rates (P=0.013). CABSI rates were higher in Seoul (P=0.001) and in medical ICUs (P=0.026). VAP rates were lower in ICUs of hospitals with more than 900 beds compared with hospitals with 400-699 beds (P=0.026). VAP rates were higher in surgical ICUs (P<0.0001) and increased 1.13-fold with each 100-unit increase in beds per infection control professional (P=0.003). The organisational and institutional characteristics of ICUs may influence DAI rates and there is a need for improvement in the incidence of VAP, CAUTI or CABSI.
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Kang B, Woo JH, Choi E, Lee HH, Kim ES, Kim J, Hwang TJ, Park YS, Kim DH, Wu JW. Optical switching of near infrared light transmission in metamaterial-liquid crystal cell structure. OPTICS EXPRESS 2010; 18:16492-16498. [PMID: 20721037 DOI: 10.1364/oe.18.016492] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
A metamaterial-liquid crystal cell structure is fabricated with the metamaterial as one of the liquid crystal alignment layers. Nano-sized double-split ring resonator in the metamaterial accommodates two distinct resonances in the near infrared regime. By adopting an azo-nematic liquid crystal in a twisted nematic liquid crystal cell structure, a photo-isomerization process is utilized to achieve an optical switching of light transmissions between two resonances. A single device of the metamaterial-liquid crystal cell structure has a potential application in the photonic switching in optical fiber telecommunications.
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Yu F, Li R, Ai L, Edington C, Yu H, Barr M, Kim ES, Hsiai TK. Electrochemical impedance spectroscopy to assess vascular oxidative stress. Ann Biomed Eng 2010; 39:287-96. [PMID: 20652746 DOI: 10.1007/s10439-010-0127-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2010] [Accepted: 07/09/2010] [Indexed: 10/19/2022]
Abstract
Vascular inflammatory responses are intimately linked with oxidative stress, favoring the development of pre-atherosclerotic lesions. We proposed that oxidized low density lipoprotein (oxLDL) and foam cell infiltrates in the subendothelial layer engendered distinct electrochemical properties that could be measured in terms of the electrochemical impedance spectroscopy (EIS). Concentric bipolar microelectrodes were applied to interrogate EIS of aortas isolated from fat-fed New Zealand White (NZW) rabbits and explants of human aortas. Frequency-dependent EIS measurements were assessed between 10 kHz and 100 kHz, and were significantly elevated in the pre-atherosclerotic lesions in which oxLDL and macrophage infiltrates were prevalent (At 100 kHz: aortic arch lesion=26.7±2.7 kΩ vs. control=15.8±2.4 kΩ; at 10 kHz: lesions=49.2±7.3 kΩ vs. control=27.6±2.7 kΩ, n=10, p<0.001). Similarly, EIS measurements were significantly elevated in the human descending aorta where pre-atherosclerotic lesions or fatty streaks were prominent. EIS measurements remained unchanged in spite of various depths of electrode submersion or orientation of the specimens. Hence, the concentric bipolar microelectrodes provided a reliable means to measure endoluminal electrochemical modifications in regions of pro-inflammatory with high spatial resolution and reproducibility albeit uneven lesion topography and non-uniform current distribution.
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Sakai H, Gamo T, Kim ES, Tsutsumi M, Tanaka T, Ishibashi J, Wakita H, Yamano M, Oomori T. Venting of carbon dioxide-rich fluid and hydrate formation in mid-okinawa trough backarc basin. Science 2010; 248:1093-6. [PMID: 17733370 DOI: 10.1126/science.248.4959.1093] [Citation(s) in RCA: 232] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Carbon dioxide-rich fluid bubbles, containing approximately 86 percent CO(2), 3 percent H(2)S, and 11 percent residual gas (CH(4) + H(2)), were observed to emerge from the sea floor at 1335- to 1550-m depth in the JADE hydrothermal field, mid-Okinawa Trough. Upon contact with seawater at 3.8 degrees C, gas hydrate immediately formed on the surface of the bubbles and these hydrates coalesced to form pipes standing on the sediments. Chemical composition and carbon, sulfur, and helium isotopic ratios indicate that the CO(2)-rich fluid was derived from the same magmatic source as dissolved gases in 320 degrees C hydrothermal solution emitted from a nearby black smoker chimney. The CO(2)-rich fluid phase may be separated by subsurface boiling of hydrothermal solutions or by leaching of CO(2)-rich fluid inclusion during posteruption interaction between pore water and volcanogenic sediments.
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Kang B, Choi E, Lee HH, Kim ES, Woo JH, Kim J, Hong TY, Kim JH, Wu JW. Polarization angle control of coherent coupling in metamaterial superlattice for closed mode excitation. OPTICS EXPRESS 2010; 18:11552-11561. [PMID: 20589016 DOI: 10.1364/oe.18.011552] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
A superlattice structure of planar metamaterial is fabricated, where the orientation of double-split ring resonators is altered in a periodic way. A time-domain terahertz transmission spectrum shows an enhanced Q-factor resonance appears when a closed mode is selectively excited by angular tuning of polarization direction. The polarization-angle selective resonance in metamaterial superlattice has a potential application in the selective field enhancement for spectroscopy.
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Kim ES, Keum B, Seo YS, Jeen YT, Chun HJ, Um SH, Kim CD, Ryu HS, Hyun JH. Intramural esophageal dissection resolved by endoscopic treatment. Endoscopy 2010; 41 Suppl 2:E313-4. [PMID: 19921607 DOI: 10.1055/s-0029-1215256] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
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Kim ES, Chang JH, Choi HS, Kim J, Lee SK. Diagnostic yield of double-dose gadobutrol in the detection of brain metastasis: intraindividual comparison with double-dose gadopentetate dimeglumine. AJNR Am J Neuroradiol 2010; 31:1055-8. [PMID: 20110372 DOI: 10.3174/ajnr.a2010] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Accurate assessment of the number and lesion characteristics of brain metastasis is very important in GKS. The purpose of this study was to compare the diagnostic efficacy of DD gadobutrol in the detection of brain metastases compared with a DD 0.5-mol/L gadolinium contrast, gadopentetate dimeglumine. MATERIALS AND METHODS Records of 27 patients (male to female ratio, 15:12; mean age, 57.1 years) diagnosed with brain metastasis and having undergone GKS were retrospectively analyzed. All patients underwent the first 3D-T1-GRE MR imaging with a DD of gadopentetate dimeglumine. The second MR imaging with a DD of gadobutrol was performed during GKS by using the same parameters used for the first scan. Two neuroradiologists counted the number of enhancing lesions on 2 consecutive MR imaging examinations and reached consensus. Lesion-brain CNR was measured from 45 lesions, and paired t test analysis was performed between DD gadopentetate dimeglumine and gadobutrol MR imaging. RESULTS On DD gadopentetate dimeglumine-enhanced images, a total of 130 lesions were detected visually. With DD gadobutrol, 25 additional lesions were detected on GKS MR imaging. There was no missing lesion on DD gadobutrol MR imaging. The mean lesion-brain CNR was higher on DD gadobutrol MR imaging than on DD gadopentetate dimeglumine imaging (2.17 +/- 0.19 versus 1.90 +/- 0.26; P = .00011, paired t test, 2-tailed). Only 2 cases showed lower CNR on DD gadobutrol images: 1 with hemorrhagic metastasis from renal cell carcinoma and the other with steroid treatment after the first MR imaging. CONCLUSIONS DD 1.0-mol/L gadobutrol provides higher lesion conspicuity and enhances lesion detection in brain metastasis compared with DD 0.5-mol/L gadolinium contrast agents.
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Lee JH, Wang ZM, Kim ES, Kim NY, Park SH, Salamo GJ. Various Quantum- and Nano-Structures by III-V Droplet Epitaxy on GaAs Substrates. NANOSCALE RESEARCH LETTERS 2009; 5:308-14. [PMID: 20671787 PMCID: PMC2893769 DOI: 10.1007/s11671-009-9481-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/23/2009] [Accepted: 10/28/2009] [Indexed: 05/29/2023]
Abstract
We report on various self-assembled In(Ga)As nanostructures by droplet epitaxy on GaAs substrates using molecular beam epitaxy. Depending on the growth condition and index of surfaces, various nanostructures can be fabricated: quantum dots (QDs), ring-like and holed-triangular nanostructures. At near room temperatures, by limiting surface diffusion of adatoms, the size of In droplets suitable for quantum confinement can be fabricated and thus InAs QDs are demonstrated on GaAs (100) surface. On the other hand, at relatively higher substrate temperatures, by enhancing the surface migrations of In adatoms, super lower density of InGaAs ring-shaped nanostructures can be fabricated on GaAs (100). Under an identical growth condition, holed-triangular InGaAs nanostructures can be fabricated on GaAs type-A surfaces, while ring-shaped nanostructures are formed on GaAs (100). The formation mechanism of various nanostructures can be understood in terms of intermixing, surface diffusion, and surface reconstruction.
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Kim ES, Bol'sheva NL, Samatadze TE, Nosov NN, Nosova IV, Zelenin AV, Punina EO, Muravenko OV, Rodionov AV. [The unique genome of two-chromosome grasses Zingeria and Colpodium, its origin, and evolution]. GENETIKA 2009; 45:1506-1515. [PMID: 20058797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Chromosome C-banding and two-color fluorescent in situ hybridization (FISH) were used to compare the chromosomes, to identify the chromosomal localization of the 45S and 5S rRNA genes, and to analyze the sequences of internal transcribed spacers 1 and 2 (ITS1 and ITS2) of the 45S rRNA genes in the genomes of grasses Zingeria biebersteiniana (2n = 4), Z. pisidica, Z. trichopoda (2n = 8), Colpodium versicolor (2n = 4), and Catabrosella variegata (syn. Colpodium variegatum) (2n = 10). Differences in C-banding pattern were observed for two Z. biebersteiniana accessions from different localities. Similar C-banding patterns of chromosomes 1 and 2 were demonstrated for the Z. pisidica and Z. biebersteininana karyotypes. Chromosome C banding and localization of the 45S and 5S rRNA genes on the chromosomes of the two Zingeria species confirmed the assumption that Z. pisidica is an allotetraploid with one of the subgenomes similar to the Z. biebersteiniana genome. ITS comparisons showed that the unique two-chromosome grasses (x = 2)-Z. biebersteiniana (2n = 4), Z. trichopoda (2n = 8), Z. pisidica (2n = 8), and C. versicolor (2n = 4), which were earlier assigned to different tribes of subtribes of the family Poaceae-represent two closely related genera, the genetic distance (p-distance) between their ITSs being only 1.2-4.4%. The Zingeria species and C. versicolor formed a common clade with Catabrosella araratica (2n = 42, x = 7) on a molecular phylogenetic tree. Thus, the karyotypes of Zingeria and Colpodium, which have the lowest known basic chromosome number (x = 2), proved to be monophyletic, rather than originating from different phylogenetic lineages.
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Kim ES, Jeon SW, Park SY, Park YD, Chung YJ, Yoon SJ, Lee SY, Park JY, Bae HI, Cho CM, Tak WY, Kweon YO, Kim SK, Choi YH. Where has the tumor gone? The characteristics of cases of negative pathologic diagnosis after endoscopic mucosal resection. Endoscopy 2009; 41:739-45. [PMID: 19693749 DOI: 10.1055/s-0029-1215043] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
BACKGROUND AND STUDY AIMS Discrepancies can occur between the histopathological findings from forceps biopsy and endoscopic mucosal resection (EMR), and occasionally in embarrassing cases tumorous tissue is not found at EMR. The aim of the present study was to evaluate the clinical, endoscopic, and histological features of gastric tumors in patients with pathololgically negative findings at EMR. PATIENTS AND METHODS We retrospectively reviewed data from all patients with gastric tumor treated with EMR or endoscopic submucosal dissection (ESD) between August 1999 and April 2007 at our institution, and enrolled into the study patients with no tumor tissue found at mucosal resection. Their biopsy and EMR specimen slides were reviewed by a single pathologist. Patient characteristics, including demographic and clinical features, and the endoscopic appearance of mucosal lesions were evaluated. RESULTS Out of 633 patients treated with EMR or ESD, 20 patients (3.2 %) were included. The mean +/- SD maximal dimension of the mucosal lesions was 6.40 +/- 2.19 mm (range 3 - 10). Mean number of forceps biopsy fragments was 3.80 +/- 1.96 and mean sampling ratio was 2.08 +/- 1.07 mm/fragment. Before resection, histological findings from forceps biopsy were: 13 low grade dysplasias (65.0 %), 2 high grade dysplasias (10.0 %), and 5 intramucosal carcinomas (25.0 %). CONCLUSIONS In the case of pathologically negative findings at EMR, tumors might have been small enough to have been removed by the previous forceps biopsy. However, the possibility of sampling error or of a different location should be considered. Furthermore, appropriate communication between endoscopists and pathologists is essential.
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Ai L, Yu H, Takabe W, Paraboschi A, Yu F, Kim ES, Li R, Hsiai TK. Optimization of intravascular shear stress assessment in vivo. J Biomech 2009; 42:1429-1437. [PMID: 19457490 DOI: 10.1016/j.jbiomech.2009.04.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2009] [Revised: 03/31/2009] [Accepted: 04/04/2009] [Indexed: 11/29/2022]
Abstract
The advent of microelectromechanical systems (MEMS) sensors has enabled real-time wall shear stress (WSS) measurements with high spatial and temporal resolution in a 3-D bifurcation model. To optimize intravascular shear stress assessment, we evaluated the feasibility of catheter/coaxial wire-based MEMS sensors in the abdominal aorta of the New Zealand white (NZW) rabbits. Theoretical and computational fluid dynamics (CFD) analyses were performed. Fluoroscope and angiogram provided the geometry of aorta, and the Doppler ultrasound system provided the pulsatile flow velocity for the boundary conditions. The physical parameters governing the shear stress assessment in NZW rabbits included (1) the position and distance from which the MEMS sensors were mounted to the terminal end of coaxial wire or the entrance length, (L(e)), (2) diameter ratios of aorta to the coaxial wire (D(aorta) /D(coaxial wire)=1.5-9.5), and (3) the range of Reynolds numbers (116-1550). At an aortic diameter of 2.4mm and a maximum Reynolds number of 212 (a mean Reynolds number of 64.2), the time-averaged shear stress (tau(ave)) was computed to be 10.06 dyn cm(-2) with a systolic peak at 33.18 dyn cm(-2). In the presence of a coaxial wire (D(aorta)/D(coaxial wire)=6 and L(e)=1.18 cm), the tau(ave) value increased to 15.54 dyn cm(-2) with a systolic peak at 51.25 dyn cm(-2). Real-time intravascular shear stress assessment by the MEMS sensor revealed an tau(ave) value of 11.92 dyn cm(-2) with a systolic peak at 47.04 dyn cm(-2). The difference between CFD and experimental tau(ave) was 18.5%. These findings provided important insights into packaging the MEMS sensors to optimize in vivo shear stress assessment.
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Jung SI, Lee CS, Park KH, Kim ES, Kim YJ, Kim GS, Lim DS, Moon JE, Min JJ, Bom HS, Jung MH, Chang YJ, Chae SL, Lee JH. Sero-epidemiology of hepatitis A virus infection among healthcare workers in Korean hospitals. J Hosp Infect 2009; 72:251-7. [PMID: 19446368 DOI: 10.1016/j.jhin.2009.03.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2009] [Accepted: 03/18/2009] [Indexed: 11/17/2022]
Abstract
Hepatitis A virus (HAV) has been increasingly reported in Korea as has an outbreak in Korean healthcare workers (HCWs). This 2008 study evaluated the sero-epidemiology of HAV infections among 3696 HCWs in four Korean hospitals. HCWs were tested for immunoglobulin G anti-HAV antibodies using commercially available kits. Data including demographic characteristics, occupation, workplace and serological status for other hepatitis viruses were collected. Statistical analyses were conducted to identify variables related to HAV seropositivity. Among the 3696 participants, 2742 (74%) were women and the majority (96%) were aged 20-39 years (median: 28; range: 19-68). Eighteen percent were physicians, 46% nurses, 10% nurses' aides, 11% paramedical technicians and 15% administrative staff. Seropositivity for HAV significantly increased with age (P<0.001): 1.8% for < or =24 years, 14.7% for 25-29 years, 41.8% for 30-34 years, 75.5% for 35-39 years, and 93.7% for > or =40 years. Among those aged 20-39 years, age-specific HAV seroprevalence was significantly lower in physicians than in the other occupational groups (P<0.001). In Korea, mass vaccination to HCWs aged < or =29 years or screening for seropositivity and vaccinating non-immune subjects aged 30-39 years should be considered, especially in physicians.
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Kim ES, Kang DH. Microwave dielectric properties of (A2+(1/3)B5+(2/3))0.5Ti0(0.5)O2 (A2+ = Zn, Mg, B5+ = Nb, Ta) ceramics. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2008; 55:1069-1074. [PMID: 18519214 DOI: 10.1109/tuffc.2008.758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Dielectric properties of (A(2+)(1/3)B(5+)(2/3))(0.5)Ti0(0.5)O(2) (A(2+) = Zn, Mg, B(5+) = Nb, Ta) ceramics were investigated at microwave frequencies. A single phase with tetragonal rutile structure was obtained through the entire compositions. Dielectric properties were strongly dependent on the structural characteristics. The specimens with B(5+) = Nb showed a larger dielectric constant than those with B(5+) = Ta due to the decrease of bond valence. Quality factors (Qf) of the specimens with B(5+) = Ta were larger than those with B(5+) = Nb. Temperature coefficient of the resonant frequencies (TCF) of (Zn(1/3)Nb(2/3) )0(0.5)Ti0(0.5)O(2) was larger than that of (Mg(1/3)Ta(2/3))0(0.5)Ti0(0.5)O(2). These results could be attributed to the changes of the temperature coefficient of dielectric constant and the degree of oxygen octahedral distortion.
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Cannata JM, Williams JA, Zhou QF, Sun L, Shung KK, Yu H, Kim ES. Self-focused ZnO transducers for ultrasonic biomicroscopy. JOURNAL OF APPLIED PHYSICS 2008; 103:84109-841094. [PMID: 19479005 PMCID: PMC2685215 DOI: 10.1063/1.2907716] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2008] [Accepted: 02/14/2008] [Indexed: 05/18/2023]
Abstract
A simple fabrication technique was developed to produce high frequency (100 MHz) self-focused single element transducers with sputtered zinc oxide (ZnO) crystal films. This technique requires the sputtering of a ZnO film directly onto a curved backing substrate. Transducers were fabricated by sputtering an 18 mum thick ZnO layer on 2 mm diameter aluminum rods with ends shaped and polished to produce a 2 mm focus or f-number equal to one. The aluminum rod served a dual purpose as the backing layer and positive electrode for the resultant transducers. A 4 mum Parylene matching layer was deposited on the transducers after housing and interconnect. This matching layer was used to protect the substrate and condition the transfer of acoustic energy between the ZnO film and the load medium. The pulse-echo response for a representative transducer was centered at 101 MHz with a -6 dB bandwidth of 49%. The measured two way insertion loss was 44 dB. A tungsten wire phantom and an adult zebrafish eye were imaged to show the capability of these transducers.
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Cong PQ, Kim ES, Song ES, Yi YJ, Park CS. Effects of fusion/activation methods on development of embryos produced by nuclear transfer of porcine fetal fibroblast. Anim Reprod Sci 2008; 103:304-11. [PMID: 17215095 DOI: 10.1016/j.anireprosci.2006.12.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2006] [Revised: 12/05/2006] [Accepted: 12/06/2006] [Indexed: 11/27/2022]
Abstract
The present studies were carried out to investigate the effects of intensity of dc pulse, number of dc pulse and equilibration before fusion/activation on developmental ability of porcine embryos derived from nuclear transfer. In experiment 1, different fusion/activation intensity (two dc pulses of 0.4, 0.8, 1.2, 1.6 and 2.0 kV/cm for 30 micros, respectively) was carried out to investigate development of embryos. In experiment 2, the reconstructed oocytes were fused and activated with one, two or three dc pulses of 1.2 kV/cm for 30 micros. In experiment 3, reconstructed oocytes were equilibrated in TCM-199 medium for 0-6 h, respectively, and fused/activated with one dc pulse of 1.2 kV/cm for 30 micros. The reconstructed embryos were cultured in PZM-3 medium containing 0.3% BSA. When oocytes were fused with donor cell by two dc pulses of 0.4 kV/cm for 30 micros, the rates of cleavage and blastocyst formation were significantly lower (32.9% and 2.5%) than those of fused by 0.8 kV/cm (59.0% and 17.4%) or 1.2 kV/cm (63.3% and 18.4%), respectively. One dc pulse of 1.2 kV/cm for 30 micros was enough to fuse and activate embryos to develop to blastocyst (24.8%). Equilibration for 2-3 h in TCM-199 before fusion/activation was beneficial for improving the developmental ability of embryos produced by nuclear transfer (25.6-23.3% at blastocysts).
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Cannata JM, Williams JA, Zhou QF, Sun L, Shung KK, Yu H, Kim ES. Self-focused ZnO transducers for ultrasonic biomicroscopy. JOURNAL OF APPLIED PHYSICS 2008; 103:artno084109. [PMID: 18596925 PMCID: PMC2442463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
A simple fabrication technique was developed to produce high frequency (100 MHz) self-focused single element transducers with sputtered zinc oxide (ZnO) crystal films. This technique requires the sputtering of a ZnO film directly onto a curved backing substrate. Transducers were fabricated by sputtering an 18 μm thick ZnO layer on 2 mm diameter aluminum rods with ends shaped and polished to produce a 2 mm focus or f-number equal to one. The aluminum rod served a dual purpose as the backing layer and positive electrode for the resultant transducers. A 4 μm Parylene matching layer was deposited on the transducers after housing and interconnect. This matching layer was used to protect the substrate and condition the transfer of acoustic energy between the ZnO film and the load medium. The pulse-echo response for a representative transducer was centered at 101 MHz with a -6 dB bandwidth of 49%. The measured two way insertion loss was 44 dB. A tungsten wire phantom and an adult zebrafish eye were imaged to show the capability of these transducers.
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Tan W, Zou Q, Kim ES, Loeb GE. Sensing human arm posture with implantable sensors. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2004:4290-3. [PMID: 17271253 DOI: 10.1109/iembs.2004.1404195] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In order to achieve functionally useful movement, sensory information is required for control of neuromuscular activation. This paper describes implantable sensor modalities to replace normal proprioceptors in feedback control. They can be packaged into miniature, wireless neural stimulators called BIONs. Sensing techniques and strategies for analyzing and combining various sensor signals are presented. These sensors include a DC accelerometer and RF magnetic sensor. Several sensor system configurations are proposed to accommodate different clinical requirements and real-time measurement of the position and orientation of human arms.
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Kim ES, Kim SH, Kim KW, Park JW, Kim YS, Sohn MH, Kim KE. Basement membrane thickening and clinical features of children with asthma. Allergy 2007; 62:635-40. [PMID: 17508967 DOI: 10.1111/j.1398-9995.2007.01375.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Asthma is a chronic inflammatory disease, characterized by airway inflammation, bronchial hyper-responsiveness, and airway obstruction. Although asthma induces partially reversible airway obstruction, obstruction can sometimes become irreversible. This may be a consequence of airway remodeling, which includes a number of structural changes, such as epithelial detachment, basement membrane (BM) thickening, smooth muscle hypertrophy, and new vessel formation. This study evaluated children with asthma for the presence of BM thickening. METHODS Eighteen children with asthma and 24 control subjects underwent flexible bronchoscopy with endobronchial biopsy. Light microscopy was used to measure BM thickness in paraffin-embedded biopsy sections. The association between BM thickening and age, sex, duration of asthma, asthma severity, FEV(1), FEV(1)/FVC, FEF(25-75%), methacholine PC(20), eosinophil count, and presence of atopy was examined. RESULTS Basement membrane thickness was greater in subjects with asthma (8.3 +/- 1.4 microM) than in control subjects (6.8 +/- 1.3 microM, P = 0.0008). Multiple regression analysis revealed that sex, FEV(1)/FVC, total IgE, and atopy (IgE for Dermatophagoides pteronyssinus >0.34 kUA/l) were significant predictive factors for BM thickness. There was no significant association between BM thickness and age, duration of asthma, FEV(1), FEF(25-75%), methacholine PC(20), eosinophil count, or asthma severity. CONCLUSIONS Basement membrane thickening has been known to be present in children with asthma. In addition, we report an association between BM thickness and sex, FEV(1)/FVC, total IgE, and the presence of IgE specific to D. pteronyssinus.
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Zheng S, El-Naggar AK, Kim ES, Kurie JM, Lozano G. A genetic mouse model for metastatic lung cancer with gender differences in survival. Oncogene 2007; 26:6896-904. [PMID: 17486075 DOI: 10.1038/sj.onc.1210493] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Lung cancer is a devastating disease with poor prognosis. The design of better therapies for lung cancer patients would be greatly aided by good mouse models that closely resemble the human disease. Unfortunately, current models for lung adenocarcinoma are inadequate due to the absence of metastases. In this study, we incorporated both K-ras and p53 missense mutations into the mouse genome and established a more faithful genetic model for human lung adenocarcinoma, the most common type of lung cancer. Mice with both mutations developed advanced lung adenocarcinomas that were highly aggressive and metastasized to multiple intrathoracic and extrathoracic sites in a pattern similar to that of human lung cancer. These mice also showed a gender difference in cancer-related death. Additionally, the presence of both mutations induced pleural mesotheliomas in 23% of these mice. This mouse model recapitulates the metastatic nature of human lung cancer and will be invaluable to further probe the molecular basis of metastatic lung cancer and for translational studies.
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Song TW, Sohn MH, Kim ES, Kim KW, Kim KE. Increased serum thymus and activation-regulated chemokine and cutaneous T cell-attracting chemokine levels in children with atopic dermatitis. Clin Exp Allergy 2006; 36:346-51. [PMID: 16499646 DOI: 10.1111/j.1365-2222.2006.02430.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Thymus and activation-regulated chemokine (TARC) and cutaneous T cell-attracting chemokine (CTACK) are responsible for the trafficking of T helper type 2 lymphocytes into sites of allergic inflammation. OBJECTIVE We tested whether these cytokines are useful markers for childhood atopic dermatitis (AD), and evaluated age-related differences in the levels of these chemokines. METHODS Serum TARC and CTACK levels, total serum IgE levels, total eosinophil counts, and specific IgE levels were measured in 401 children. The patients were characterized as having atopic eczema (n=157), non-atopic eczema (n=107), or as healthy control subjects (n=137). RESULTS Both TARC and CTACK levels in children with AD were significantly higher than those in healthy control subjects. Serum TARC and CTACK levels significantly correlated with disease severity both in children with atopic eczema and in children with non-atopic eczema. Serum TARC levels in children with AD significantly correlated with their serum CTACK levels. Serum TARC and CTACK levels decreased in accordance with their ages. CONCLUSION Serum TARC and CTACK levels might be useful markers for disease severity both in children with atopic eczema and with non-atopic eczema. Serum TARC and CTACK levels decreased in accordance with their ages.
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Kim ES, Kim JW, Kim YT, Kim SY, Ko YS, Shim YJ, Chung EJ, Lee‐Kim YC. Serum Phospholipid‐Fatty Acid Patterns and Antioxidant Status in Cervical Cancer Patients. FASEB J 2006. [DOI: 10.1096/fasebj.20.4.a152-c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Rodionov AV, Tiupa NB, Kim ES, Machs EM, Loskutov IG. [Genomic structure of the autotetraploid oat species Avena macrostachya inferred from comparative analysis of the ITS1 and ITS2 sequences: on the oat karyotype evolution during the early stages of the Avena species divergence]. GENETIKA 2005; 41:646-56. [PMID: 15977816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
To examine the genomic structure of Avena macrostachya, internal transcribed spacers, ITS1 and ITS2, as well as nuclear 5.8S tRNA genes from three oat species with AsAs karyotype (A. wiestii, A. hirtula, and A. atlantica), and those from A. longiglumis (AlAl), A. canariensis (AcAc), A. ventricosa (CvCv), A. pilosa, and A. clauda (CpCp) were sequenced. All species of the genus Avena examined represented a monophyletic group (bootstrap index = 98), within which two branches, i.e., species with A- and C-genomes, were distinguished (bootstrap indices = 100). The subject of our study, A. macrostachya, albeit belonging to the phylogenetic branch of C-genome oat species (karyotype with submetacentic and subacrocentric chromosomes), has preserved an isobrachyal karyotype, (i.e., that containing metacentric chromosomes), probably typical of the common Avena ancestor. It was suggested to classify the A. macrostachya genome as a specific form of C-genome, Cm-genome. Among the species from other genera studied, Arrhenatherum elatius was found to be the closest to Avena in ITS1 and ITS structure. Phylogenetic relationships between Avena and Helictotrichon remain intriguingly uncertain. The HPR389153 sequence from H. pratense genome was closest to the ITS1 sequences specific to the Avena A-genomes (p-distance = 0.0237), while the differences of this sequence from the ITS1 of A. macrostachya reached 0.1221. On the other hand, HAD389117 from H. adsurgens was close to the ITS1 specific to Avena C-genomes (p-distance = 0.0189), while its differences from the A-genome specific ITS1 sequences reached 0.1221. It seems likely that the appearance of highly polyploid (2n = 12-21x) species of H. pratense and H. adsurgens could be associated with interspecific hybridization involving Mediterranean oat species carrying A- and C-genomes. A hypothesis on the pathways of Avena chromosomes evolution during the early stages the oat species divergence is proposed.
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Kim ES, Han SM, Kim YI, Song KH, Kim MS, Kim WB, Park JY, Lee KU. Prevalence and clinical characteristics of metabolic syndrome in a rural population of South Korea. Diabet Med 2004; 21:1141-3. [PMID: 15384963 DOI: 10.1111/j.1464-5491.2004.01398.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AIMS To determine the prevalence of metabolic syndrome according to the criteria of the Adult Treatment Panel III (ATP III) and the World Health Organization (WHO). METHODS Data were collected from 1108 subjects over 40 years of age in the Chongup district, a rural area of South Korea. We evaluated the prevalence and clinical characteristics of metabolic syndrome according to the two criteria. RESULTS According to the ATP III criteria, the prevalence of central obesity was 0.2% in men and 27.3% in women, which is much lower than the prevalence of central obesity in Americans. However, the prevalence of metabolic syndrome was similar to the prevalence in Americans. Of the Korean subjects over 40 years of age, 29.4% and 39.2% had metabolic syndrome according to the ATP III and WHO criteria, respectively. Metabolic syndrome according to the ATP III criteria was associated with insulin resistance, but not with microalbuminuria. CONCLUSIONS Metabolic syndrome has a high prevalence in South Koreans despite the low prevalence of obesity and/or central obesity.
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Ahn CS, Kim ES. Effect of alpha-tocopherol and taurine supplementation on oxidized LDL levels of middle aged Korean women during aerobic exercise. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2004; 526:269-76. [PMID: 12908610 DOI: 10.1007/978-1-4615-0077-3_34] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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