51
|
Baik YO, Choi SK, Olveda RM, Espos RA, Ligsay AD, Montellano MB, Yeam JS, Yang JS, Park JY, Kim DR, Desai SN, Singh AP, Kim IY, Kim CW, Park SN. A randomized, non-inferiority trial comparing two bivalent killed, whole cell, oral cholera vaccines (Euvichol vs Shanchol) in the Philippines. Vaccine 2015; 33:6360-5. [PMID: 26348402 DOI: 10.1016/j.vaccine.2015.08.075] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Revised: 07/27/2015] [Accepted: 08/28/2015] [Indexed: 11/17/2022]
Abstract
BACKGROUND Currently, there are two oral cholera vaccines (OCV) that are prequalified by the World Health Organization. Both (Dukoral and Shanchol) have been proven to be safe, immunogenic, and effective. As the global supply of OCV remains limited, we assessed the safety and immunogenicity of a new low cost, killed, bivalent OCV (Euvichol) in the Philippines. METHODS The randomized controlled trial was carried out in healthy Filipino adults and children. Two doses of either the current WHO prequalified OCV (Shanchol) or the same composition OCV being considered for WHO prequalification (Euvichol) were administered to participants. RESULTS The pivotal study was conducted in total of 1263 healthy participants (777 adults and 486 children). No serious adverse reactions were elicited in either vaccine groups. Vibriocidal antibody responses to V. cholerae O1 Inaba following administration of two doses of Euvichol were non-inferior to those of Shanchol in adults (82% vs 76%) and children (87% vs 89%). Similar findings were observed for O1 Ogawa in adults (80% vs 74%) and children (91% vs 88%). CONCLUSION A two dose schedule with Euvichol induces a strong vibriocidal response comparable to those elicited by the currently WHO prequalified OCV, Shanchol. Euvichol will be an oral cholera vaccine suitable for use in lower income countries, where cholera still has a significant economic and public health impact.
Collapse
|
52
|
Choi SK, Park S, Choi Y, Moon HS. Early intracellular signaling events induced by in vitro metreleptin administration in cardiac myocytes and uterine smooth muscle cells. Cell Mol Biol (Noisy-le-grand) 2015; 61:15-20. [PMID: 26255263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 07/20/2015] [Indexed: 06/04/2023]
Abstract
Intracellular signaling pathways regulated by leptin have largely been studied in metabolically important organs such as adipose tissue and peripheral blood mononuclear cells, suggesting that leptin plays a key role in pathophysiology of insulin resistance. However, whether synthetic analog of leptin, metreleptin, has similar effects on cardiac myocytes (CM) and uterine smooth muscle cells (USMC) has not yet been studied. Hence, in order to address these questions, we extended previous observations and investigated in vitro signaling study whether metreleptin may activate key signaling pathways. We observed that metreleptin activates Jak2 and STAT3 signaling pathways in dose- and time-dependent manner in CM and USMC. Also, we found that metreleptin increases ERK1/2, JNK and/or p38 phosphorylation in CM. In vitro metreleptin administration also increased ERK1/2 and/or p38 phosphorylation in USMC. By contrast, JNK was not regulated by in vitro metreleptin administration in USMC. Moreover, metreleptin-activated all signaling pathways were blocked by pre-treatment of PD98095 (ERK inhibitor), SB203580 (p38 inhibitor) and/or SP600125 (JNK inhibitor), respectively. Finally, metreleptin increased cell size (hypertrophy) in both CM and USMC. Our data provide novel insights into the role of Jak2, STAT3, ERK1/2, JNK and/or p38 as probable mediators of the action of leptin in regulating hypertrophy in CM and USMC.
Collapse
|
53
|
Choi SK, Hong YO, Lee WM, Kim EK, Joo JE, Kim DW, Lee H. Overexpression of PI3K-p110α in the progression of uterine cervical neoplasia and its correlation with pAkt and DJ-1. EUR J GYNAECOL ONCOL 2015; 36:389-393. [PMID: 26390688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
OBJECTIVE To investigate the expression of PI3K-p110α, pAkt, PTEN, the signaling molecules from PI3K/Akt signaling pathway, DJ-1, an oncoprotein and HSP90a, a molecular chaperone, and their correlation in uterine cervical neoplasia, in order to elucidate their role in cervical carcinogenesis. MATERIALS AND METHODS Using immunohistochemistry, the authors analyzed the expression of PI3K-p110α, pAkt, PTEN, DJ-1 and HSP90α, and their correlation in ten normal tissues, cervical intraepithelial neoplasia (CIN) including 30 CIN1 and 31 CIN3, and 33 cases of invasive squamous cell carcinoma (SCC). RESULTS The expression of all proteins significantly increased in CIN3 compared to CIN1, and only the expression of PI3K-p110α significantly increased in invasive SCC compared to CIN3. There was a significant positive correlation between the expression of PI3K-p110α and DJ-1, as well as PI3K-p110α and pAkt in CIN3 and invasive SCC. CONCLUSION Overexpression of PI3K-p110α is associated with progression of uterine cervical neoplasia, and the expression of pAkt and DJ-1 is positively correlated with PI3K-p110α expression in this process.
Collapse
|
54
|
Baik YO, Choi SK, Kim JW, Yang JS, Kim IY, Kim CW, Hong JH. Safety and immunogenicity assessment of an oral cholera vaccine through phase I clinical trial in Korea. J Korean Med Sci 2014; 29:494-501. [PMID: 24753695 PMCID: PMC3991791 DOI: 10.3346/jkms.2014.29.4.494] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Accepted: 02/14/2014] [Indexed: 11/20/2022] Open
Abstract
The safety, tolerability and immunogenicity of an oral cholera vaccine (OCV) was assessed in adult Korean male through an open-label, non-comparative clinical study. Two doses of vaccine with an interval of 2 weeks were given to 20 healthy subjects. A total of 7 adverse events occurred in 6 subjects. However, no clinically significant change was observed in electrocardiograms, vital signs, physical examinations, and clinical laboratory tests. The immunogenicity of OCV was evaluated by serum vibriocidal assay where anti-Vibrio cholerae O1 and O139 antibodies were measured at day 0, 14, and 28 of vaccine administration. The antibody titers ranged from < 2.5-5,120 for V. cholerae O1 Inaba, < 2.5-10,240 for V. cholerae O1 Ogawa and < 2.5-480 for V. cholerae O139. In addition, the fold increase in antibody titers ranged from 1-4,096 for O1 Inaba, 1-8,192 for O1 Ogawa, and 1-384 for O139. The seroconversion rate was 95% and 45% for O1 and O139 antibodies, respectively. Our study clearly shows that administration of two doses of OCV at a 2 week-interval increases an appropriate level of antibody titer in the serum of healthy Korean adult males (Clinical Trial Number, NCT01707537).
Collapse
|
55
|
Yoon JY, Choi GS, Cho IS, Choi SK. First Report of Cucumber mosaic virus in Saintpaulia ionantha in Korea. PLANT DISEASE 2014; 98:573. [PMID: 30708706 DOI: 10.1094/pdis-08-13-0847-pdn] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
African violet (Saintpaulia ionantha) is an ornamental species of the family Gesneriaceae and is characterized by fleshy leaves and colorful flowers. This popular, exotic ornamental, originally from Kenya and Tanzania, is vegetatively produced from cutting and tissue culture (1). In May 2013, virus-like foliar symptoms, including a mosaic with dark green islands and chlorosis surrounding the veins, were observed on an African violet plant in a greenhouse located in Icheon, Korea. Cucumber mosaic virus (CMV) was identified in the symptomatic plant by serological testing for the presence of CMV coat protein (CP) with a commercial immunostrip kit (Agdia, Elkhart, IN). The presence of CMV was confirmed by serological detection with a commercially available double-antibody sandwich (DAS)-ELISA kit (Agdia). Sap from the serologically positive sample was mechanically inoculated to test plants using 10 mM phosphate buffer (pH 7.0). The virus (named CMV-AV1) caused necrotic local lesions on Chenopodium amaranticolor at 5 days post-inoculation (dpi), while mild to severe mosaic was observed in Nicotiana glutinosa, N. tabacum 'Samsun NN,' Cucurbita pepo 'Super-Top,' Physalis angulate, and Solanum lycopersicum 'Unicorn' 10 to 14 dpi. Examination of the inoculated plant leaves by DAS-ELISA and electron microscopy (leaf dips) showed positive reactions to CMV and the presence of spherical virions ∼28 nm in diameter, respectively. To verify whether CMV-AV1 is the cause of disease symptoms observed in African violet, virus-free African violet (10 plants) was mechanically inoculated by sap from local lesions on C. amaranticolor inoculated with CMV-AV1. At 8 weeks after inoculation, all plants produced systemic mosaic and chlorosis surrounding veins, resulting in strong DAS-ELISA reactions for CMV, whereas mock-inoculated African violet plants remained symptomless and virus-free. The presence of CMV-AV1 in all naturally infected and mechanically inoculated plants was further verified by reverse transcription (RT)-PCR. Total RNAs were extracted with the RNeasy Plant Mini Kit (Qiagen, Hilden, Germany), according to the manufacturer's instructions. RT-PCR was carried out with the One-Step RT-PCR Kit (Invitrogen, Carlsbad, CA) using a pair of primers, CPTALL3 and CPTALL5 (2), amplifying the entire CP gene and part of an intergenic region and 3'-noncoding region of CMV RNA3. RT-PCR products (960 bp) were obtained from all naturally infected and mechanically inoculated plants as well as from positive control (viral RNAs from virions), but not from healthy tissues. The amplified RT-PCR products were purified with QIAquick PCR Purification Kit (Qiagen) and sequenced using BigDye Termination kit (Applied Biosystems, Foster City, CA). Multiple alignment of the CMV-AV1 CP sequence (Accession No. AB842275) with CP sequences of other CMV isolates using MEGA5 software revealed that 91.8 to 99.0% and 71.0 to 73.0% identities to those of CMV subgroup I and subgroup II, respectively. These results provide additional confirmation of CMV-AV1 infection. CMV may pose a major threat for production of African violet since the farming of African violet plants is performed using the vegetative propagation of the African violet leaves in Korea. In particular, mosaic and chlorosis symptoms in African violet cause damage to ornamental quality of African violet. To our knowledge, this is the first report of CMV infection of African violet in the world. References: (1) S. T. Baatvik. Fragm. Flor. Geobot. Suppl. 2:97, 1993. (2) S. K. Choi et al. J. Virol. Methods 83:67, 1999.
Collapse
|
56
|
Cho IS, Choi GS, Choi SK, Seo EY, Lim HS. First Report of Cherry necrotic rusty mottle virus Infecting Sweet Cherry Trees in Korea. PLANT DISEASE 2014; 98:164. [PMID: 30708591 DOI: 10.1094/pdis-07-13-0723-pdn] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Cherry necrotic rusty mottle virus (CNRMV), an unassigned member in the family Betaflexiviridae, has been reported in sweet cherry in North America, Europe, New Zealand, Japan, China, and Chile. The virus causes brown, angular necrotic spots, shot holes on the leaves, gum blisters, and necrosis of the bark in several cultivars (1). During the 2012 growing season, 154 sweet cherry trees were tested for the presence of CNRMV by RT-PCR. Samples were randomly collected from 11 orchards located in Gyeonggi and Gyeongsang provinces in Korea. RNA was extracted from leaves using the NucliSENS easyMAG system (bioMérieux, Boxtel, The Netherlands). The primer pair CGRMV1/2 (2) was used to amplify the coat protein region of CNRMV. Although none of the collected samples showed any notable symptoms, CNRMV PCR products of the expected size (949 bp) were obtained from three sweet cherry samples from one orchard in Gyeonggi province. The PCR products were cloned into a pGEM-T easy vector (Promega, Madison, WI) and sequenced. BLAST analyses of the three Korean sequences obtained (GenBank Accession Nos. AB822635, AB822636, and AB822637) showed 97% nucleotide sequence identity with a flowering cherry isolate from Japan (EU188439), and shared 98.8 to 99.6% nucleotide and 99.6 to 100% amino acid similarities to each other. The CNRMV positive samples were also tested for Apple chlorotic leaf spot virus (ACLSV), Cherry mottle leaf virus (CMLV), Cherry rasp leaf virus (CRLV), Cherry leafroll virus (CLRV), Cherry virus A (CVA), Little cherry virus 1 (LChV-1), Prune dwarf virus (PDV), and Prunus necrotic ringspot virus (PNRSV) by RT-PCR. One of the three CNRMV-positive samples was also infected with CVA. To confirm CNRMV infection by wood indexing, Prunus serrulata cv. Kwanzan plants were graft-inoculated with chip buds from the CNRMV-positive sweet cherry trees. At 3 to 4 weeks post-inoculation, the Kwanzan plants showed quick decline with leaves wilting and dying; CNRMV infection of the indicators was confirmed by RT-PCR. To our knowledge, this is the first report of CNRMV infection of sweet cherry trees in Korea. Screening for CNRMV in propagation nurseries should minimize spread of this virus within Korea. References: (1) R. Li and R. Mock. Arch. Virol. 153:973, 2008. (2) R. Li and R. Mock. J. Virol. Methods 129:162, 2005.
Collapse
|
57
|
Choi SK, Coldea R, Kolmogorov AN, Lancaster T, Mazin II, Blundell SJ, Radaelli PG, Singh Y, Gegenwart P, Choi KR, Cheong SW, Baker PJ, Stock C, Taylor J. Spin waves and revised crystal structure of honeycomb iridate Na2IrO3. PHYSICAL REVIEW LETTERS 2012; 108:127204. [PMID: 22540621 DOI: 10.1103/physrevlett.108.127204] [Citation(s) in RCA: 123] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2011] [Indexed: 05/31/2023]
Abstract
We report inelastic neutron scattering measurements on Na2IrO3, a candidate for the Kitaev spin model on the honeycomb lattice. We observe spin-wave excitations below 5 meV with a dispersion that can be accounted for by including substantial further-neighbor exchanges that stabilize zigzag magnetic order. The onset of long-range magnetic order below T(N)=15.3 K is confirmed via the observation of oscillations in zero-field muon-spin rotation experiments. Combining single-crystal diffraction and density functional calculations we propose a revised crystal structure model with significant departures from the ideal 90° Ir-O-Ir bonds required for dominant Kitaev exchange.
Collapse
|
58
|
Chen CXR, Chan SL, Law TC, Choi SK, Chan KH. Secondary prevention of stroke: an evidence-based clinical audit in the primary care. Hong Kong Med J 2011; 17:469-477. [PMID: 22147317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023] Open
Abstract
OBJECTIVE To audit secondary preventive care in non-acute stroke patients in a local General Outpatient Clinic of the Hospital Authority. DESIGN Comparison of two samples from a case series at different time-points. SETTING General Outpatient Clinic, Hong Kong. PATIENTS Non-acute stroke patients fulfilling the inclusion criteria and regularly followed up in a local General Outpatient Clinic during the audit cycle were recruited. Evidence-based audit criteria and performance standards were established after thorough literature review. A sample from this case series was compared retrospectively at two time-points. First-phase evaluation was performed in October 2009 and deficiencies were identified. After 9 months of active intervention, second-phase evaluation was performed in July 2010. Chi squared test and student's t test were used to compare the significance of relevant changes noted. RESULTS First-phase data showed marked deficiencies in proper assessment of cardiovascular risk factors. Satisfactory blood pressure, glucose and lipid control was evident only in 47% of the hypertensive, 45% of the diabetic, and 37% of the dyslipidaemic stroke patients, respectively. After 9 months of implementing changes, significant improvements were noted with respect to standard targets being achieved. In the second phase, more comprehensive tackling of cardiovascular risk factors was noted, with satisfactory blood pressure control in 73% of hypertensive patients, and adequate metabolic control in 62% diabetic patients (P<0.01 for both). Only 59% of the dyslipidaemic stroke patients had optimal lipid control, though their mean low-density lipoprotein concentration was significantly reduced (P<0.05). CONCLUSION This study provided a valuable lesson in identifying deficiencies in secondary prevention for stroke patients managed in a local primary care facility. Using a team approach intervention, quality assurance was promoted and a definite impact on patient care was demonstrated.
Collapse
|
59
|
Jung HJ, Sir JJ, Lee HK, Kang YK, Song BG, Choi SK. Very late thrombosis of sirolimus-eluting stent despite dual antiplatelet therapy for 4 years in a patient with lung cancer. Minerva Cardioangiol 2011; 59:113-116. [PMID: 21285937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
|
60
|
Chung KW, Suh BC, Cho SY, Choi SK, Kang SH, Yoo JH, Hwang JY, Choi BO. Early-onset Charcot-Marie-Tooth patients with mitofusin 2 mutations and brain involvement. J Neurol Neurosurg Psychiatry 2010; 81:1203-6. [PMID: 20587496 DOI: 10.1136/jnnp.2009.181669] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Mutations of the mitofusin 2 (MFN2) gene have been reported to be the most common cause of the axonal form of Charcot-Marie-Tooth disease (CMT). A prospective brain MRI study was performed on 18 early-onset CMT patients with MFN2 mutations, and a high frequency (39%) of brain abnormalities was found. Early-onset patients showed multiple scattered or confluent brain lesions that involved gray matter as well as white matter. Patterns of brain involvement in early-onset patients differed from those of late-onset patients and other hereditary peripheral neuropathies. In addition, one CMT patient demonstrated a brain lesion before the development of peripheral neuropathy.
Collapse
|
61
|
Kim HJ, Choi SK, Kang SH, Oh KH. Fatigue measurement system designed for a chalcogenide-based device using a homemade heater tip. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2008; 79:115101. [PMID: 19045907 DOI: 10.1063/1.3010380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A fatigue measurement system is designed using a homemade tungsten (W) heater tip. This system is composed of a pulse generator and an atomic force microscope with the W heater tip attached. Also included are a parameter analyzer and control devices. The entire measurement process is controlled by a designed program without communication errors. Additionally, a process to fabricate the sharp W heater tip that applies an electrical pulse and evaluates the electrical properties is introduced. The analysis of the tip, carried out by scanning electron microscopy and electron backscattering diffraction, shows that the tip has great thermomechanical stability. Using this fatigue measurement system, the resistance of the Ge(2)Sb(2)Te(5) (GST) cell was successfully measured as a function of the number of set/reset cycles. The specific area (both program area and failure area) was easily observed. It is expected that the expansion of GST is a source of information regarding the fatigue of a GST cell.
Collapse
|
62
|
Yang RY, Zou RP, Yu AB, Choi SK. Characterization of interparticle forces in the packing of cohesive fine particles. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2008; 78:031302. [PMID: 18851026 DOI: 10.1103/physreve.78.031302] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2008] [Indexed: 05/26/2023]
Abstract
We numerically investigate force structures in the packing of fine cohesive particles using the discrete element method. By changing the particle size and therefore the van der Waals force, the effect of cohesion on the normal contact force and the total normal force, which is the sum of the normal contact forces and the van der Waals forces, is analyzed. It is shown that, with decreasing particle size, the normal contact forces become more uniform and have a narrower and more symmetric distribution, while the distributions of the total normal forces widen. Spatial correlation between the interparticle forces exists for the packing of coarse noncohesive particles. As the particle size decreases, this correlation becomes weaker for the contact forces but stronger for the total normal forces. A comparison between the effective weight of particles and the internal force structure suggests that there are differences between the particle-particle and particle-wall forces. The bimodal distribution of the effective weight indicates that there may exist two phases in the packings when cohesion is present, governed by the compressive and tensile stresses.
Collapse
|
63
|
Yang RY, Zou RP, Yu AB, Choi SK. Pore structure of the packing of fine particles. J Colloid Interface Sci 2006; 299:719-25. [PMID: 16563414 DOI: 10.1016/j.jcis.2006.02.041] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2005] [Revised: 02/16/2006] [Accepted: 02/18/2006] [Indexed: 11/18/2022]
Abstract
This paper presents a numerical study of the pore structure of fine particles. By means of granular dynamics simulation, packings of mono-sized particles ranging from 1 to 1000 microm are constructed. Our results show that packing density varies with particle size due to the effect of the cohesive van der Waals force. Pores and their connectivity are then analysed in terms of Delaunay tessellation. The geometries of the pores are represented by the size and shape of Delaunay cells and quantified as a function of packing density or particle size. It shows that the cell size decreases and the cell shape becomes more spherical with increasing packing density. A general correlation exists between the size and shape of cells: the larger the cell size relative to particle size, the more spherical the cell shape. This correlation, however, becomes weaker as packing density decreases. The connectivity between pores is represented by throat size and channel length. With decreasing packing density, the throat size increases and the channel length decreases. The pore scale information would be useful to understand and model the transport and mechanical properties of porous media.
Collapse
|
64
|
Choi SK, Lee JY, Kwon DY, Cho KJ. Settling characteristics of problem algae in the water treatment process. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2006; 53:113-9. [PMID: 16752771 DOI: 10.2166/wst.2006.214] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
The settling velocity or removal rates of problem algae in the water treatment process and their flocculants were measured with settling column (SETCOL) and fluorometric method. Our research who were centred on the algal density and shape affecting the settling. The settling velocities of large algae ranged from 0.1 cm/h to 2.6 cm/h, whereas those of small algae were below 1.0 cm/h. The settlings of algae in the stationary growth phase significantly increased and dead algae corresponded with the declining algae. The extent of deformation, which was expressed as the coefficient of form resistance of the algae had the great influences upon the settling. The most extreme deformed algae were needle-shaped ones like Synedra acus, which was known to be a problem in water treatment processes in Korea. Changes in the settling velocity of algae were correlated with algal volume and morphology rather than cell density.
Collapse
|
65
|
Kim P, Kim DH, Kim B, Choi SK, Lee SH, Khademhosseini A, Langer R, Suh KY. Fabrication of nanostructures of polyethylene glycol for applications to protein adsorption and cell adhesion. NANOTECHNOLOGY 2005; 16:2420-2426. [PMID: 20818029 DOI: 10.1088/0957-4484/16/10/072] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
A simple method was developed to fabricate polyethylene glycol (PEG) nanostructures using capillary lithography mediated by ultraviolet (UV) exposure. Acrylate-containing PEG monomers, such as PEG dimethacrylate (PEG-DMA, MW = 330), were photo-cross-linked under UV exposure to generate patterned structures. In comparison to unpatterned PEG films, hydrophobicity of PEG nanostructure modified surfaces was significantly enhanced. This could be attributed to trapped air in the nanostructures as supported by water contact angle measurements. Proteins (fibronectin, immunoglobulin, and albumin) and cells (fibroblasts and P19 EC cells) were examined on the modified surfaces to test for the level of protein adsorption and cell adhesion. It was found that proteins and cells preferred to adhere on nanostructured PEG surfaces in comparison to unpatterned PEG films; however, this level of adhesion was significantly lower than that of glass controls. These results suggest that capillary lithography can be used to fabricate PEG nanostructures capable of modifying protein and cell adhesive properties of surfaces.
Collapse
|
66
|
Park CH, Joo YE, Kim HS, Choi SK, Rew JS, Kim SJ. A prospective, randomized trial of endoscopic band ligation versus endoscopic hemoclip placement for bleeding gastric Dieulafoy's lesions. Endoscopy 2004; 36:677-81. [PMID: 15280971 DOI: 10.1055/s-2004-825661] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND STUDY AIMS Dieulafoy's lesion is a rare cause of massive gastrointestinal hemorrhage, most commonly in the proximal stomach. Mechanical endoscopic methods have recently become the standard therapeutic approach. However, there have been few studies comparing the efficacy of different mechanical endoscopic methods in treating gastric Dieulafoy's lesions. This study was therefore carried out to compare the hemostatic efficacy and safety of endoscopic band ligation (EBL) and endoscopic hemoclip placement (EHP) in the treatment of bleeding gastric Dieulafoy's lesions. PATIENTS AND METHODS Between January 2002 and October 2003, 26 consecutive patients with bleeding gastric Dieulafoy's lesions were prospectively enrolled and were randomly assigned to undergo EBL (13 patients) or EHP (13 patients). Demographic characteristics, endoscopic variables, and outcome parameters, including rates of hemostasis and recurrent bleeding, were analyzed. RESULTS One O-ring was applied in each case in the EBL group, and the median number of hemoclips applied was one (range one to four) in the EHP group. There were no significant differences between the groups with regard to age, sex, presence of shock, initial hemoglobin level, coagulopathy, concurrent diseases, location of the lesion, type of bleeding stigmata, blood transfusion requirements, or hospitalization periods. Primary hemostasis was achieved in all 26 patients. There was one case of recurrent bleeding in each group; secondary hemostasis was achieved with EBL in one of these patients and by endoscopic epinephrine injection in the other. There were no second episodes of recurrent bleeding, no procedure-related complications, no cases in which surgery was needed, and no bleeding-related deaths in either group. CONCLUSIONS In this small study, no differences were detected in the efficacy or the safety of EBL vs. EHP in the management of bleeding gastric Dieulafoy's lesions.
Collapse
|
67
|
Abe K, Abe K, Abe N, Abe T, Adachi I, Aihara H, Akai K, Akatsu M, Akemoto M, Asano Y, Aso T, Aulchenko V, Aushev T, Bakich AM, Ban Y, Banerjee S, Bay A, Bedny I, Bizjak I, Bondar A, Bozek A, Bracko M, Browder TE, Chao Y, Chen KF, Cheon BG, Chistov R, Choi SK, Choi Y, Chuvikov A, Cole S, Danilov M, Dragic J, Drutskoy A, Eidelman S, Eiges V, Enari Y, Epifanov D, Flanagan J, Furukawa K, Gabyshev N, Garmash A, Gershon T, Golob B, Haba J, Hara K, Hastings NC, Hayashii H, Hazumi M, Hinz L, Hokuue T, Hoshi Y, Hou WS, Hsiung YB, Huang HC, Iijima T, Ikeda H, Inami K, Ishikawa A, Ishino H, Itoh R, Iwasaki H, Iwasaki M, Iwasaki Y, Kakuno H, Kamitani T, Kang JH, Kang JS, Kapusta P, Kataoka SU, Katayama N, Kawai H, Kawasaki T, Kibayashi A, Kichimi H, Kikutani E, Kim HJ, Kim JH, Kim SK, Kinoshita K, Koppenburg P, Korpar S, Krizan P, Krokovny P, Kumar S, Kuzmin A, Kwon YJ, Lange JS, Leder G, Lee SH, Lee YJ, Lesiak T, Li J, Limosani A, Lin SW, Liventsev D, MacNaughton J, Mandl F, Marlow D, Matsumoto H, Matsumoto T, Matyja A, Michizono S, Mimashi T, Mitaroff W, Miyabayashi K, Miyake H, Miyata H, Mohapatra D, Moloney GR, Murakami A, Nagamine T, Nagasaka Y, Nakadaira T, Nakamura TT, Nakano E, Nakao M, Nakazawa H, Natkaniec Z, Neichi K, Nishida S, Nitoh O, Noguchi S, Nozaki T, Ogawa S, Ogawa Y, Ohmi K, Ohshima T, Ohuchi N, Oide K, Okabe T, Okuno S, Olsen SL, Ostrowicz W, Ozaki H, Pakhlov P, Palka H, Park CW, Park H, Parslow N, Piilonen LE, Root N, Rozanska M, Sagawa H, Sakai Y, Schneider O, Schümann J, Schwanda C, Schwartz AJ, Semenov S, Senyo K, Shibuya H, Shidara T, Shwartz B, Sidorov V, Singh JB, Soni N, Stamen R, Stanic S, Staric M, Sugahara R, Sumisawa K, Sumiyoshi T, Suzuki K, Suzuki S, Tajima O, Takasaki F, Tamai K, Tamura N, Tanaka M, Tawada M, Teramoto Y, Tomura T, Tsuboyama T, Tsukamoto T, Uehara S, Uglov T, Ueno K, Unno Y, Uno S, Varner G, Varvell KE, Wang CC, Wang CH, Wang MZ, Watanabe Y, Yabsley BD, Yamada Y, Yamaguchi A, Yamashita Y, Yamauchi M, Yanai H, Yang H, Ying J, Yokoyama M, Yoshida M, Yusa Y, Zhang CC, Zhang ZP, Ziegler T, Zontar D, Zürcher D. Observation of large CP violation and evidence for direct CP violation in B0-->pi(+)pi(-) decays. PHYSICAL REVIEW LETTERS 2004; 93:021601. [PMID: 15323897 DOI: 10.1103/physrevlett.93.021601] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2004] [Indexed: 05/24/2023]
Abstract
We report the first observation of CP violation in B0-->pi(+)pi(-) decays based on 152x10(6) gamma (4S)-->BB decays collected with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. We reconstruct a B0-->pi(+)pi(-) CP eigenstate and identify the flavor of the accompanying B meson from its decay products. From the distribution of the time intervals between the two B meson decay points, we obtain A(pipi)=+0.58+/-0.15(stat)+/-0.07(syst) and S(pipi)=-1.00+/-0.21(stat)+/-0.07(syst). We rule out the CP-conserving case, A(pipi)=S(pipi)=0, at a level of 5.2 standard deviations. We also find evidence for direct CP violation with a significance at or greater than 3.2 standard deviations for any S(pipi) value.
Collapse
|
68
|
Park CH, Lee WS, Joo YE, Choi SK, Rew JS, Kim SJ. Endoscopic band ligation for control of acute peptic ulcer bleeding. Endoscopy 2004; 36:79-82. [PMID: 14722860 DOI: 10.1055/s-2004-814121] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
BACKGROUND AND STUDY AIMS The use of endoscopic band ligation (EBL) is being extended to treat various causes of upper and lower gastrointestinal bleeding. The aim of this study was to evaluate the usefulness of EBL for control of acute peptic ulcer bleeding and to define the lesions that are most suitable for this technique. PATIENTS AND METHODS 19 patients with major stigmata of acute peptic ulcer bleeding were treated using EBL; 11 patients had active bleeding and eight patients had a nonbleeding visible vessel. RESULTS The site of acute peptic ulcer bleeding was the stomach in 12 patients, the duodenum in four patients, and Billroth II anastomosis in three. Initial hemostasis was achieved in 19 patients (100 %) in a single session. There were no rebleeding episodes in any of the patients, and there was no bleeding-related or procedure-related death. During long-term outpatient follow-up, bleeding did not recur. CONCLUSIONS EBL is an effective and safe endoscopic treatment for small-sized nonfibrotic acute peptic ulcer bleeding. Larger studies in patients with acute peptic ulcer bleeding are needed to confirm these promising results.
Collapse
|
69
|
Dever TE, Roll-Mecak A, Choi SK, Lee JH, Cao C, Shin BS, Burley SK. Universal translation initiation factor IF2/eIF5B. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 2003; 66:417-24. [PMID: 12762044 DOI: 10.1101/sqb.2001.66.417] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
70
|
Park CH, Sohn YH, Lee WS, Joo YE, Choi SK, Rew JS, Kim SJ. The usefulness of endoscopic hemoclipping for bleeding Dieulafoy lesions. Endoscopy 2003; 35:388-92. [PMID: 12701008 DOI: 10.1055/s-2003-38780] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND STUDY AIMS Dieulafoy lesion is a rare cause of massive gastrointestinal hemorrhage, most commonly from the proximal stomach. Surgery was regarded as the treatment of choice in the past, but recently endoscopic management has become the standard approach. However, the effectiveness of various endoscopic modalities in treating bleeding Dieulafoy lesion has been little studied. This study was therefore done to compare the hemostatic efficacy of endoscopic hemoclipping and epinephrine injection therapy. PATIENTS AND METHODS Between January 1998 and December 2001, a consecutive series of 32 patients with bleeding Dieulafoy lesion underwent endoscopic treatment. They were randomly treated either by endoscopic epinephrine injection therapy (n = 16) or by hemoclipping (n = 16). We compared mortality rate, primary hemostasis rate, and rebleeding rate between two groups. RESULTS There was no bleeding-related death in either group. There was no significant difference in primary hemostasis rates between the hemoclipping group (93.8 %) and epinephrine injection group (87.5 %, P = 1.00). There was a trend toward a lower rate of need for multiple endoscopic sessions to achieve permanent hemostasis in the hemoclipping group compared with the epinephrine injection group (6.3 % vs. 31.3 %, P = 0.086). Hemoclipping was significantly more effective in preventing recurrent bleeding than epinephrine injection therapy (0 % vs. 35.7 %, P < 0.05). With regard to lesion site, hemoclipping was significantly more effective in preventing recurrent bleeding of gastric body Dieulafoy lesion than epinephrine injection therapy (0 % vs. 50 %, P < 0.05). CONCLUSIONS Bleeding from Dieulafoy lesion was well controlled by therapeutic endoscopic procedures. Hemoclipping was more effective for Dieulafoy lesion than epinephrine injection therapy, with less need for subsequent endoscopy.
Collapse
|
71
|
Joo YE, Kim HS, Choi SK, Rew JS, Kim HR, Cho CK, Kim SJ. Internal hernia presenting as obstructive jaundice and acute pancreatitis. Scand J Gastroenterol 2002; 37:983-6. [PMID: 12229977 DOI: 10.1080/003655202760230982] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We report the first case of obstructive jaundice and acute pancreatitis caused by herniation of the small bowel through the foramen of Winslow in a 45-year-old man. Abdominal computed tomography (CT) and magnetic resonance imaging (MRI) revealed dilated small-bowel loops positioned in the gastrohepatic space, dilatation of the gallbladder and both intrahepatic bile ducts, and mild swelling of the pancreas. A small-bowel series revealed a cluster of small-bowel loops in the mid-upper abdomen, with displacement of the stomach to the left. At laparotomy, there was an internal herniation of jejunal loop through the defect of gastrocolic ligament into the lesser sac and finally passing through the foramen of Winslow. The common bile duct was compressed externally by the herniated bowel and the pancreas was mildly swollen. To the best of our knowledge, these complications of internal hernia have not been reported previously.
Collapse
|
72
|
Yun KW, Choi SK. Mycorrhizal colonization and plant growth affected by aqueous extract of Artemisia princeps var. orientalis and two phenolic compounds. J Chem Ecol 2002; 28:353-62. [PMID: 11925073 DOI: 10.1023/a:1017990309629] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The effects of an aqueous extract of Artemisia princeps var. orientalis and two phenolic compounds on mycorrhizal colonization and plant growth have been investigated. Greenhouse studies showed that the inhibitory effect of the extract on mycorrhizal colonization and plant growth increased in proportion to the concentration of the extract. When the mycorrhizal test plants were treated with an increasing concentration of phenolic compounds, the mycorrhizal colonization in roots of the test plant and the plant growth were decreased. There were strong indications that mycorrhizal fungi mitigated the inhibitory influence of shoot extract of A. princeps var. orientalis and phenolic compounds.
Collapse
|
73
|
Joo YE, Kim HS, Choi SK, Rew JS, Park CS, Kim YJ, Kim SJ. Massive gastrointestinal bleeding caused by ectopic pancreas mimicking jejunal tumor. Digestion 2002; 64:133-6. [PMID: 11684829 DOI: 10.1159/000048853] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Ectopic pancreas is usually an incidental finding at surgery or autopsy and rarely produces clinical symptoms. But it is capable of producing symptoms, depending on its location, size and involvement of the overlying mucosa. CASE REPORT We report a case with massive gastrointestinal bleeding from ectopic pancreas mimicking jejunal tumor, confirmed by emergency operation. A 40-year-old male was admitted to Chonnam National University Hospital with a 2-day history of melena. A technetium-99m-labeled RBC scan showed massive radioactivity in loops of small bowel due to active bleeding. Superior mesenteric angiography revealed a hypervascular stained mass supplied by proximal jejunal branch. A computed tomographic scan of abdomen revealed an enhancing mass in the proximal jejunum. At emergency operation, bleeding from the center of the mass was found situated approximately 30 cm from the Treitz ligament. Segmental resection of the involved jejunum and end-to-end anastomosis were performed. Histologic examination of resected specimen revealed an ectopic pancreas. CONCLUSION So far, there have been no case reports of massive gastrointestinal bleeding from ectopic pancreas mimicking jejunal tumor as described in our case. In every patient in whom ectopic pancreas can definitely be seen to cause clinical symptoms including gastrointestinal bleeding, the lesion should be excised.
Collapse
|
74
|
Han MS, Kang PW, Choi DH, Lee YH, Choi SK, Yoon SR, Shin DJ, Kim JM, Jin HJ, Kwak KD, Kim W. Korean population genetic data for eleven STR loci. Forensic Sci Int 2001; 123:230-1. [PMID: 11728753 DOI: 10.1016/s0379-0738(01)00531-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Allele frequency and forensic parameters for eleven STR loci were surveyed in a random sample from the Korean population.
Collapse
|
75
|
Cha YS, Choi SK, Suh H, Lee SN, Cho D, Li K. Effects of carnitine coingested caffeine on carnitine metabolism and endurance capacity in athletes. J Nutr Sci Vitaminol (Tokyo) 2001; 47:378-84. [PMID: 11922111 DOI: 10.3177/jnsv.47.378] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The purpose of this study was to examine whether caffeine (CAF), carnitine (CAR), or CAF+CAR mixture administration affects exercise endurance time via carnitine metabolism. Water (CON), CAF, CAR, or CAF+CAR mixture was administered to five male rugby athletes participating in this study by a randomized double-blind fashion who were made to ride a cycle ergometer for exercise. The CAF effect on exercise endurance time was small, but the CAR trial significantly increased the exercise endurance time compared with CON trial; a further CAF+CAR mixture trial had greater effects on the exercise endurance time than those of a CON, CAF, or CAR trial. A CAR or CAF+CAR mixed trial increased urinary nonesterified carnitine (NEC) and total carnitine (TCAR), but no changes were observed in acid-soluble acylcarnitine (ASAC) and acid-insoluble acylcarnitine (AIAC) excretion. A CAR or CAF+CAR mixed trial resulted in higher levels of plasma NEC, ASAC, and TCAR fractions than the CON and CAF trials did on exhaustion time. Total cholesterol, triglyceride, and free fatty acid in blood were significantly increased at exhaustion time, but they were not affected in the CAF or the CAR trial. These results suggest that carnitine ingestion could promote fat oxidation, resulting in higher endurance performance in athletes, and especially these ergogenic effects of carnitine coingested with caffeine may be greater than those of carnitine alone.
Collapse
|