1
|
Choi H, Hong J, Ha J, Kang J, Kim SY. ABFs, a family of ABA-responsive element binding factors. J Biol Chem 2000; 275:1723-30. [PMID: 10636868 DOI: 10.1074/jbc.275.3.1723] [Citation(s) in RCA: 699] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Abscisic acid (ABA) plays an important role in environmental stress responses of higher plants during vegetative growth. One of the ABA-mediated responses is the induced expression of a large number of genes, which is mediated by cis-regulatory elements known as abscisic acid-responsive elements (ABREs). Although a number of ABRE binding transcription factors have been known, they are not specifically from vegetative tissues under induced conditions. Considering the tissue specificity of ABA signaling pathways, factors mediating ABA-dependent stress responses during vegetative growth phase may thus have been unidentified so far. Here, we report a family of ABRE binding factors isolated from young Arabidopsis plants under stress conditions. The factors, isolated by a yeast one-hybrid system using a prototypical ABRE and named as ABFs (ABRE binding factors) belong to a distinct subfamily of bZIP proteins. Binding site selection assay performed with one ABF showed that its preferred binding site is the strong ABRE, CACGTGGC. ABFs can transactivate an ABRE-containing reporter gene in yeast. Expression of ABFs is induced by ABA and various stress treatments, whereas their induction patterns are different from one another. Thus, a new family of ABRE binding factors indeed exists that have the potential to activate a large number of ABA/stress-responsive genes in Arabidopsis.
Collapse
|
|
25 |
699 |
2
|
Blay JY, Bonvalot S, Casali P, Choi H, Debiec-Richter M, Dei Tos AP, Emile JF, Gronchi A, Hogendoorn PCW, Joensuu H, Le Cesne A, McClure J, Mac Clure J, Maurel J, Nupponen N, Ray-Coquard I, Reichardt P, Sciot R, Stroobants S, van Glabbeke M, van Oosterom A, Demetri GD. Consensus meeting for the management of gastrointestinal stromal tumors. Report of the GIST Consensus Conference of 20-21 March 2004, under the auspices of ESMO. Ann Oncol 2005; 16:566-78. [PMID: 15781488 DOI: 10.1093/annonc/mdi127] [Citation(s) in RCA: 485] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND The management of gastrointestinal stromal tumors (GIST) has evolved very rapidly in the last 4 years. The objectives of this international consensus meeting were to describe the optimal management procedures for patients with GIST in localized and advanced stages, as well as research issues for the future. MATERIALS AND METHODS A panel of experts from six specialties, including pathology, molecular biology, imaging, surgery, medical oncology and methodologists for clinical practice guidelines from different European and extra European sarcoma societies were invited to a 2-day workshop. Several questions were selected by the organizing committee prior to the conference. Selected panelists reviewed the current levels of evidence for each point, and presented their conclusions during the meeting. These proposals were discussed, and consensus points were identified and categorized according to the Standard Options Recommandations (SOR) of the French Federation of Cancer Centers and National Comprehensive Cancer Network (NCCN). RESULTS Thirty-two consensus points were identified, most from categories 2A of the NCCN and B2 of the SOR. Among these, the standard histological examination with immunohistochemical analysis using CD117, CD34, PS100, desmin and smooth muscle actin is considered standard. Molecular biology for the identification of KIT and PDGFRA mutation is an optional diagnostic procedure for GIST with negative CD117 staining, and otherwise is considered a research procedure. Complete tumor resection with negative tumor margins is the standard surgical treatment. Adjuvant imatinib after optimal tumor resection as well as neo-adjuvant imatinib remain experimental approaches to be performed within prospective clinical studies. Imatinib should be started at the date of diagnosis of metastatic relapse and given until development of intolerance or progressive disease. The optimal criteria for tumor response to imatinib remain to be delineated, and should include not only tumor size reduction or disease stabilization, but also reduction of tumor density (Hounsfield Units) on computed tomography and metabolic activity (i.e. reduction of FDG uptake on positron emission tomography). In a substantial proportion of patients, stable disease and even increase in tumor size may be associated with pathologic response to imatinib therapy, and available survival data indicate that the survival of these patients is similar to that of patients with conventional tumor response. Metastasis resection is an experimental procedure. CONCLUSIONS Consensus points in clinical management of GIST as well as questions for future clinical trials were identified during this consensus conference on GIST management.
Collapse
|
Review |
20 |
485 |
3
|
Choi H, Kim S, Mukhopadhyay P, Cho S, Woo J, Storz G, Ryu SE. Structural basis of the redox switch in the OxyR transcription factor. Cell 2001; 105:103-13. [PMID: 11301006 DOI: 10.1016/s0092-8674(01)00300-2] [Citation(s) in RCA: 425] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The Escherichia coli OxyR transcription factor senses H2O2 and is activated through the formation of an intramolecular disulfide bond. Here we present the crystal structures of the regulatory domain of OxyR in its reduced and oxidized forms, determined at 2.7 A and 2.3 A resolutions, respectively. In the reduced form, the two redox-active cysteines are separated by approximately 17 A. Disulfide bond formation in the oxidized form results in a significant structural change in the regulatory domain. The structural remodeling, which leads to different oligomeric associations, accounts for the redox-dependent switch in OxyR and provides a novel example of protein regulation by "fold editing" through a reversible disulfide bond formation within a folded domain.
Collapse
|
|
24 |
425 |
4
|
Fuhrer MS, Nygard J, Shih L, Forero M, Yoon YG, Mazzoni MS, Choi HJ, Ihm J, Louie SG, Zettl A, McEuen PL. Crossed nanotube junctions. Science 2000; 288:494-7. [PMID: 10775104 DOI: 10.1126/science.288.5465.494] [Citation(s) in RCA: 369] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Junctions consisting of two crossed single-walled carbon nanotubes were fabricated with electrical contacts at each end of each nanotube. The individual nanotubes were identified as metallic (M) or semiconducting (S), based on their two-terminal conductances; MM, MS, and SS four-terminal devices were studied. The MM and SS junctions had high conductances, on the order of 0.1 e(2)/h (where e is the electron charge and h is Planck's constant). For an MS junction, the semiconducting nanotube was depleted at the junction by the metallic nanotube, forming a rectifying Schottky barrier. We used two- and three-terminal experiments to fully characterize this junction.
Collapse
|
|
25 |
369 |
5
|
Choi HJ, Kang SW, Yang CH, Rhee SG, Ryu SE. Crystal structure of a novel human peroxidase enzyme at 2.0 A resolution. NATURE STRUCTURAL BIOLOGY 1998; 5:400-6. [PMID: 9587003 DOI: 10.1038/nsb0598-400] [Citation(s) in RCA: 301] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Hydrogen peroxide (H2O2) has been implicated recently as an intracellular messenger that affects cellular processes including protein phosphorylation, transcription and apoptosis. A set of novel peroxidases, named peroxiredoxins (Prx), regulate the intracellular concentration of H2O2 by reducing it in the presence of an appropriate electron donor. The crystal structure of a human Prx enzyme, hORF6, reveals that the protein contains two discrete domains and forms a dimer. The N-terminal domain has a thioredoxin fold and the C-terminal domain is used for dimerization. The active site cysteine (Cys 47), which exists as cysteine-sulfenic acid in the crystal, is located at the bottom of a relatively narrow pocket. The positively charged environment surrounding Cys 47 accounts for the peroxidase activity of the enzyme, which contains no redox cofactors.
Collapse
|
Comparative Study |
27 |
301 |
6
|
Claassen J, Jetté N, Chum F, Green R, Schmidt M, Choi H, Jirsch J, Frontera JA, Connolly ES, Emerson RG, Mayer SA, Hirsch LJ. Electrographic seizures and periodic discharges after intracerebral hemorrhage. Neurology 2007; 69:1356-65. [PMID: 17893296 DOI: 10.1212/01.wnl.0000281664.02615.6c] [Citation(s) in RCA: 293] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
OBJECTIVE To determine the frequency and significance of electrographic seizures and other EEG findings in patients with intracerebral hemorrhage (ICH). METHODS We reviewed 102 consecutive patients with ICH who underwent continuous electroencephalographic monitoring (cEEG). Demographic, clinical, radiographic, and cEEG findings were recorded. Using multivariate logistic regression analysis, we determined factors associated with 1) electrographic seizures, 2) periodic epileptiform discharges (PEDs), and 3) poor outcome (death, vegetative or minimally conscious state) at hospital discharge. RESULTS Seizures occurred in 31% (n = 32) of patients with ICH, prior to cEEG in 19 patients. Eighteen percent (n = 18) of patients had electrographic seizures; only one of these patients also had clinical seizures while on cEEG. After controlling for demographic and clinical predictors, only an increase in ICH volume of 30% or more between admission and 24-hour follow-up CT scan was associated with electrographic seizures (33% vs 15%; OR 9.5, 95% CI 1.7 to 53.8). PEDs were less frequently seen in those with hemorrhages located at least 1 mm from the cortex (8% vs 29%; OR 0.2, 95% CI 0.1 to 0.7). PEDs were independently associated with poor outcome (65% vs 17%; OR 7.6, 95% CI 2.1 to 27.3). In patients with electrographic seizures, the first seizure was detected within the first hour of cEEG monitoring in 56% and within 48 hours in 94%. CONCLUSIONS Seizures occurred in one third of patients with intracerebral hemorrhage (ICH) and over half were purely electrographic. Electrographic seizures were associated with expanding hemorrhages, and periodic discharges with cortical ICH and poor outcome. Further research is needed to determine if treating or preventing seizures or PEDs might lead to improved outcome after ICH.
Collapse
|
Journal Article |
18 |
293 |
7
|
Fisher KJ, Choi H, Burda J, Chen SJ, Wilson JM. Recombinant adenovirus deleted of all viral genes for gene therapy of cystic fibrosis. Virology 1996; 217:11-22. [PMID: 8599194 DOI: 10.1006/viro.1996.0088] [Citation(s) in RCA: 223] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Recombinant adenoviruses are being developed for gene therapy of inherited disorders such as cystic fibrosis because they efficiently transduce recombinant genes into nondividing cells in vivo. First generation recombinant adenoviruses, rendered defective by deletion of sequences spanning E1a and E1b, express low levels of early and late viral genes that activate destructive cellular immune responses. Current strategies for improving recombinant adenoviruses attempt to inactivate other essential genes through deletion and growth in new packaging cell lines or incorporation of temperature sensitive mutations which allow propagation of the virus in available packaging cell lines at permissive temperatures. We describe in this report a new type of recombinant adenovirus that is deleted of all viral open reading frames. This recombinant (called delta-rAd), which contains only the essential cis elements (i.e., ITRs and contiguous packaging sequence), is propagated in 293 cells in the presence of E1-deleted helper virus. Concatamers of the monomeric vector genome were passaged and capable of transduction. The delta-rAd genome is packaged into virions that sediment at a lower density than the helper virus in cesium gradients forming the basis for a purification protocol. A fully deleted recombinant adenovirus that expresses human cystic fibrosis transmembrane conductance regulator was produced and used to transduce human airway epithelial cells derived from a cystic fibrosis patient. Packaging and propagation of a fully deleted adenovirus is an important step toward the development of a safer vector. Improved production and purification strategies need to be developed before this new vector system can be evaluated in vivo.
Collapse
|
|
29 |
223 |
8
|
Lee S, Choi H, Suh S, Doo IS, Oh KY, Choi EJ, Schroeder Taylor AT, Low PS, Lee Y. Oligogalacturonic acid and chitosan reduce stomatal aperture by inducing the evolution of reactive oxygen species from guard cells of tomato and Commelina communis. PLANT PHYSIOLOGY 1999; 121:147-52. [PMID: 10482669 PMCID: PMC59362 DOI: 10.1104/pp.121.1.147] [Citation(s) in RCA: 212] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/1999] [Accepted: 05/12/1999] [Indexed: 05/18/2023]
Abstract
Stomatal opening provides access to inner leaf tissues for many plant pathogens, so narrowing stomatal apertures may be advantageous for plant defense. We investigated how guard cells respond to elicitors that can be generated from cell walls of plants or pathogens during pathogen infection. The effect of oligogalacturonic acid (OGA), a degradation product of the plant cell wall, and chitosan (beta-1,4-linked glucosamine), a component of the fungal cell wall, on stomatal movements were examined in leaf epidermis of tomato (Lycopersicon esculentum L.) and Commelina communis L. These elicitors reduced the size of the stomatal aperture. OGA not only inhibited light-induced stomatal opening, but also accelerated stomatal closing in both species; chitosan inhibited light-induced stomatal opening in tomato epidermis. The effects of OGA and chitosan were suppressed when EGTA, catalase, or ascorbic acid was present in the medium, suggesting that Ca(2+) and H(2)O(2) mediate the elicitor-induced decrease of stomatal apertures. We show that the H(2)O(2) that is involved in this process is produced by guard cells in response to elicitors. Our results suggest that guard cells infected by pathogens may close their stomata via a pathway involving H(2)O(2) production, thus interfering with the continuous invasion of pathogens through the stomatal pores.
Collapse
|
research-article |
26 |
212 |
9
|
Chung DR, Lee SS, Lee HR, Kim HB, Choi HJ, Eom JS, Kim JS, Choi YH, Lee JS, Chung MH, Kim YS, Lee H, Lee MS, Park CK. Emerging invasive liver abscess caused by K1 serotype Klebsiella pneumoniae in Korea. J Infect 2006; 54:578-83. [PMID: 17175028 DOI: 10.1016/j.jinf.2006.11.008] [Citation(s) in RCA: 207] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2006] [Revised: 11/07/2006] [Accepted: 11/07/2006] [Indexed: 12/20/2022]
Abstract
OBJECTIVES The high incidence of invasive liver abscess caused by Klebsiella pneumoniae in Taiwan, contrasted with the rareness of this disease in Western countries, has aroused special interest. There have been few detailed reports from other Asian countries. To investigate a current epidemiology of K. pneumoniae liver abscess in Korea and to determine K serotype distribution in K. pneumoniae strains causing liver abscess, we performed a nationwide prospective study. METHODS Community-acquired, culture-proven liver abscess cases were enrolled between 2004 and 2005. Etiologies and clinical features were analyzed. K. pneumoniae isolates were serotyped according to K antigen. Meta-analysis was done to determine the time trend of the etiologies of liver abscess in Korea. RESULTS Out of 371 cases collected prospectively, 290 (78.2%) were caused by K. pneumoniae. Most K. pneumoniae liver abscesses were monomicrobial. Diabetes mellitus was the most common underlying disease (39.9%). Distant metastatic infections were frequently observed (8.7%). magA PCR revealed that 95 (59.4%) out of 160 K. pneumoniae isolates belonged to the K1 serotype. CONCLUSIONS Our study indicates that K. pneumoniae has emerged as a major etiologic agent of liver abscess in Korea, and these emerging infections seem to be attributable to invasive K. pneumoniae strains with capsular K1 serotype.
Collapse
|
Journal Article |
19 |
207 |
10
|
Jais B, Rebours V, Malleo G, Salvia R, Fontana M, Maggino L, Bassi C, Manfredi R, Moran R, Lennon AM, Zaheer A, Wolfgang C, Hruban R, Marchegiani G, Fernández Del Castillo C, Brugge W, Ha Y, Kim MH, Oh D, Hirai I, Kimura W, Jang JY, Kim SW, Jung W, Kang H, Song SY, Kang CM, Lee WJ, Crippa S, Falconi M, Gomatos I, Neoptolemos J, Milanetto AC, Sperti C, Ricci C, Casadei R, Bissolati M, Balzano G, Frigerio I, Girelli R, Delhaye M, Bernier B, Wang H, Jang KT, Song DH, Huggett MT, Oppong KW, Pererva L, Kopchak KV, Del Chiaro M, Segersvard R, Lee LS, Conwell D, Osvaldt A, Campos V, Aguero Garcete G, Napoleon B, Matsumoto I, Shinzeki M, Bolado F, Fernandez JMU, Keane MG, Pereira SP, Acuna IA, Vaquero EC, Angiolini MR, Zerbi A, Tang J, Leong RW, Faccinetto A, Morana G, Petrone MC, Arcidiacono PG, Moon JH, Choi HJ, Gill RS, Pavey D, Ouaïssi M, Sastre B, Spandre M, De Angelis CG, Rios-Vives MA, Concepcion-Martin M, Ikeura T, Okazaki K, Frulloni L, Messina O, Lévy P. Serous cystic neoplasm of the pancreas: a multinational study of 2622 patients under the auspices of the International Association of Pancreatology and European Pancreatic Club (European Study Group on Cystic Tumors of the Pancreas). Gut 2016; 65:305-312. [PMID: 26045140 DOI: 10.1136/gutjnl-2015-309638] [Citation(s) in RCA: 206] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2015] [Accepted: 05/11/2015] [Indexed: 02/07/2023]
Abstract
OBJECTIVES Serous cystic neoplasm (SCN) is a cystic neoplasm of the pancreas whose natural history is poorly known. The purpose of the study was to attempt to describe the natural history of SCN, including the specific mortality. DESIGN Retrospective multinational study including SCN diagnosed between 1990 and 2014. RESULTS 2622 patients were included. Seventy-four per cent were women, and median age at diagnosis was 58 years (16-99). Patients presented with non-specific abdominal pain (27%), pancreaticobiliary symptoms (9%), diabetes mellitus (5%), other symptoms (4%) and/or were asymptomatic (61%). Fifty-two per cent of patients were operated on during the first year after diagnosis (median size: 40 mm (2-200)), 9% had resection beyond 1 year of follow-up (3 years (1-20), size at diagnosis: 25 mm (4-140)) and 39% had no surgery (3.6 years (1-23), 25.5 mm (1-200)). Surgical indications were (not exclusive) uncertain diagnosis (60%), symptoms (23%), size increase (12%), large size (6%) and adjacent organ compression (5%). In patients followed beyond 1 year (n=1271), size increased in 37% (growth rate: 4 mm/year), was stable in 57% and decreased in 6%. Three serous cystadenocarcinomas were recorded. Postoperative mortality was 0.6% (n=10), and SCN's related mortality was 0.1% (n=1). CONCLUSIONS After a 3-year follow-up, clinical relevant symptoms occurred in a very small proportion of patients and size slowly increased in less than half. Surgical treatment should be proposed only for diagnosis remaining uncertain after complete workup, significant and related symptoms or exceptionally when exists concern with malignancy. This study supports an initial conservative management in the majority of patients with SCN. TRIAL REGISTRATION NUMBER IRB 00006477.
Collapse
|
|
9 |
206 |
11
|
Lee D, Koh Y, Kim K, Kim B, Choi H, Kim D, Suhartono MT, Pyun Y. Isolation and characterization of a thermophilic lipase from bacillus thermoleovorans ID-1. FEMS Microbiol Lett 1999; 179:393-400. [PMID: 10518742 DOI: 10.1111/j.1574-6968.1999.tb08754.x] [Citation(s) in RCA: 187] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
A thermophilic microorganism, Bacillus thermoleovorans ID-1, isolated from hot springs in Indonesia, showed extracellular lipase activity and high growth rates on lipid substrates at elevated temperatures. On olive oil (1.5%, w/v) as the sole carbon source, the isolate ID-1 grew very rapidly at 65 degrees C with its specific growth rate (2.50 h(-1)) and its lipase activity reached the maximum value of 520 U l(-1) during the late exponential phase and then decreased. In addition to this, isolate ID-1 could grow on a variety of lipid substrates such as oils (olive oil, soybean oil and mineral oil), triglycerides (triolein, tributyrin) and emulsifiers (Tween 20, 40). The excreted lipase of ID-1 was purified 223-fold to homogeneity by ammonium sulfate precipitation, DEAE-Sephacel ion-exchange chromatography and Sephacryl S-200 gel filtration chromatography. As a result, the relative molecular mass of the lipase was determined to be 34 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The enzyme showed optimal activity at 70-75 degrees C and pH 7.5 and exhibited 50% of its original activity after 1 h incubation at 60 degrees C and 30 min at 70 degrees C and its catalytic function was activated in the presence of Ca(2+) or Zn(2+).
Collapse
|
|
26 |
187 |
12
|
Naito E, Roland PE, Grefkes C, Choi HJ, Eickhoff S, Geyer S, Zilles K, Ehrsson HH. Dominance of the right hemisphere and role of area 2 in human kinesthesia. J Neurophysiol 2004; 93:1020-34. [PMID: 15385595 DOI: 10.1152/jn.00637.2004] [Citation(s) in RCA: 183] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We have previously shown that motor areas are engaged when subjects experience illusory limb movements elicited by tendon vibration. However, traditionally cytoarchitectonic area 2 is held responsible for kinesthesia. Here we use functional magnetic resonance imaging and cytoarchitectural mapping to examine whether area 2 is engaged in kinesthesia, whether it is engaged bilaterally because area 2 in non-human primates has strong callosal connections, which other areas are active members of the network for kinesthesia, and if there is a dominance for the right hemisphere in kinesthesia as has been suggested. Ten right-handed blindfolded healthy subjects participated. The tendon of the extensor carpi ulnaris muscles of the right or left hand was vibrated at 80 Hz, which elicited illusory palmar flexion in an immobile hand (illusion). As control we applied identical stimuli to the skin over the processus styloideus ulnae, which did not elicit any illusions (vibration). We found robust activations in cortical motor areas [areas 4a, 4p, 6; dorsal premotor cortex (PMD) and bilateral supplementary motor area (SMA)] and ipsilateral cerebellum during kinesthetic illusions (illusion-vibration). The illusions also activated contralateral area 2 and right area 2 was active in common irrespective of illusions of right or left hand. Right areas 44, 45, anterior part of intraparietal region (IP1) and caudo-lateral part of parietal opercular region (OP1), cortex rostral to PMD, anterior insula and superior temporal gyrus were also activated in common during illusions of right or left hand. These right-sided areas were significantly more activated than the corresponding areas in the left hemisphere. The present data, together with our previous results, suggest that human kinesthesia is associated with a network of active brain areas that consists of motor areas, cerebellum, and the right fronto-parietal areas including high-order somatosensory areas. Furthermore, our results provide evidence for a right hemisphere dominance for perception of limb movement.
Collapse
|
Research Support, Non-U.S. Gov't |
21 |
183 |
13
|
Lee JY, Choi HJ, Park IN, Hong SB, Oh YM, Lim CM, Lee SD, Koh Y, Kim WS, Kim DS, Kim WD, Shim TS. Comparison of two commercial interferon- assays for diagnosing Mycobacterium tuberculosis infection. Eur Respir J 2006; 28:24-30. [PMID: 16611658 DOI: 10.1183/09031936.06.00016906] [Citation(s) in RCA: 178] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The clinical usefulness of ex vivo interferon-gamma assays may largely depend on the assay format and epidemiological status of tuberculosis (TB) in the region studied. From July 2004 to June 2005 a prospective comparison study was undertaken at a tertiary referral hospital in South Korea. The results of tuberculin skin tests (TST) and the commercially available QuantiFERON-TB Gold (QFT-G) and T SPOT-TB (SPOT) assays were compared in an intermediate TB-burden country. Of the 224 participants studied, results from all three tests (TST, QFT-G, and SPOT) were available in 218; 87 with active TB and 131 at a low risk for TB. Using 10 mm as a cut-off for TST, SPOT sensitivity (96.6%) was significantly higher than that seen for TST (66.7%) and QFT-G (70.1%). QFT-G showed superior specificity over TST (91.6 versus 78.6%). Although the specificity of QFT-G was higher than that of SPOT (91.6 versus 84.7%), the difference was not statistically significant. Whilst some differences were found in the performance of the two commercialised interferon-gamma assays, they seemed to be superior in their detection of Mycobacterium tuberculosis infection compared with tuberculin skin tests. The most appropriate choice of interferon-gamma assay to use may depend on the clinical setting.
Collapse
|
|
19 |
178 |
14
|
Kim JM, Lee JS, Choi H, Sohn D, Ahn DJ. Rational Design and in-Situ FTIR Analyses of Colorimetrically Reversibe Polydiacetylene Supramolecules. Macromolecules 2005. [DOI: 10.1021/ma051551i] [Citation(s) in RCA: 178] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
|
20 |
178 |
15
|
Spray DC, Fujita M, Saez JC, Choi H, Watanabe T, Hertzberg E, Rosenberg LC, Reid LM. Proteoglycans and glycosaminoglycans induce gap junction synthesis and function in primary liver cultures. J Biophys Biochem Cytol 1987; 105:541-51. [PMID: 2886511 PMCID: PMC2114879 DOI: 10.1083/jcb.105.1.541] [Citation(s) in RCA: 171] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Intercellular communication via gap junctions, as measured by dye and electrical coupling, disappears within 12 h in primary rat hepatocytes cultured in serum-supplemented media or within 24 h in cells in a serum-free, hormonally defined medium (HDM) designed for hepatocytes. Glucagon and linoleic acid/BSA were the primary factors in the HDM responsible for the extended life span of the electrical coupling. After 24 h of culture, no hormone or growth factor tested could restore the expression of gap junctions. After 4-5 d of culture, the incidence of coupling was undetectable in a serum-supplemented medium and was only 4-5% in HDM alone. However, treatment with glycosaminoglycans or proteoglycans of 24-h cultures, having no detectable gap junction protein, resulted in synthesis of gap junction protein and of reexpression of electrical and dye coupling within 48 h. Most glycosaminoglycans were inactive (heparan sulfates, chondroitin-6 sulfates) or only weakly active (dermatan sulfates, chondroitin 4-sulfates, hyaluronates), the weakly active group increasing the incidence of coupling to 10-30% with the addition of 50-100 micrograms/ml of the factor. Treatment of the cells with 50-100 micrograms/ml of heparins derived from lung or intestine resulted in cells with intermediate levels of coupling (30-50%). By contrast, 10-20 micrograms/ml of chondroitin sulfate proteoglycan, dermatan sulfate proteoglycan, or liver-derived heparin resulted in dye coupling in 80-100% of the cells, with numerous cells showing dye spread from a single injected cell. Sulfated polysaccharides of glucose (dextran sulfates) or of galactose (carrageenans) were inactive or only weakly active except for lambda-carrageenan, which induced up to 70% coupling (albeit no multiple coupling in the cultures). The abundance of mRNA (Northern blots) encoding gap junction protein and the amounts of the 27-kD gap junction polypeptide (Western blots) correlated with the degree of electrical and dye coupling indicating that the active glycosaminoglycans and proteoglycans are inducing synthesis and expression of gap junctions. Thus, proteoglycans and glycosaminoglycans, especially those found in abundance in the extracellular matrix of liver cells, are important in the regulation of expression of gap junctions and, thereby, in the regulation of intercellular communication in the liver. The relative potencies of heparins from different tissue sources at inducing gap junction expression are suggestive of functional tissue specificity for these glycosaminoglycans.
Collapse
|
research-article |
38 |
171 |
16
|
Kim JK, Huh SO, Choi H, Lee KS, Shin D, Lee C, Nam JS, Kim H, Chung H, Lee HW, Park SD, Seong RH. Srg3, a mouse homolog of yeast SWI3, is essential for early embryogenesis and involved in brain development. Mol Cell Biol 2001; 21:7787-95. [PMID: 11604513 PMCID: PMC99948 DOI: 10.1128/mcb.21.22.7787-7795.2001] [Citation(s) in RCA: 158] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2001] [Accepted: 08/15/2001] [Indexed: 11/20/2022] Open
Abstract
Srg3 (SWI3-related gene product) is a mouse homolog of yeast SWI3, Drosophila melanogaster MOIRA (also named MOR/BAP155), and human BAF155 and is known as a core subunit of SWI/SNF complex. This complex is involved in the chromatin remodeling required for the regulation of transcriptional processes associated with development, cellular differentiation, and proliferation. We generated mice with a null mutation in the Srg3 locus to examine its function in vivo. Homozygous mutants develop in the early implantation stage but undergo rapid degeneration thereafter. An in vitro outgrowth study revealed that mutant blastocysts hatch, adhere, and form a layer of trophoblast giant cells, but the inner cell mass degenerates after prolonged culture. Interestingly, about 20% of heterozygous mutant embryos display defects in brain development with abnormal organization of the brain, a condition known as exencephaly. Histological examination suggests that exencephaly is caused by the failure in neural fold elevation, resulting in severe brain malformation. Our findings demonstrate that Srg3 is essential for early embryogenesis and plays an important role in the brain development of mice.
Collapse
|
research-article |
24 |
158 |
17
|
Abstract
PURPOSE The purpose of this report is to describe the biceps load test II for evaluating the superior labral anterior and posterior (SLAP) lesions. TYPE OF STUDY This is a double-blind study in consecutive data, which includes diagnostic accuracy of a test using sensitivity, specificity, and interexaminer reliability. METHODS In the supine position, the arm is elevated to 120 degrees and externally rotated to its maximal point, with the elbow in the 90 degrees flexion and the forearm in the supinated position. The patient is asked to flex the elbow while resisting the elbow flexion by the examiner. The test is considered positive if the patient complains of pain during the resisted elbow flexion. The test is negative if pain is not elicited or if the pre-existing pain during the elevation and external rotation of the arm is unchanged or diminished by the resisted elbow flexion. A prospective study was performed in 127 patients to evaluate the diagnostic accuracy for the biceps load test II. Two independent examiners were assigned to perform the new diagnostic test. The results of the tests were confirmed during the arthroscopic examination. RESULTS A positive test result in 38 subjects correlated with a SLAP lesion in 35 patients and an intact biceps-superior labrum in 3 patients. A negative test result in 89 patients correlated with an intact superior labrum complex in 85 patients, whereas 4 patients with a negative test result had a type II SLAP lesion. The biceps load test II had a sensitivity of 89.7%, a specificity of 96.9%, a positive-predictive value of 92.1%, a negative-predictive value of 95.5%, and a kappa coefficient of 0.815. The abduction and external rotation of the shoulder during the test changes the relative direction of the biceps fiber in a position of oblique angle to the posterosuperior labrum. The resisted contraction of the biceps increases the pain generated on the superior labrum that is already peeled off the glenoid margin in the abducted and externally rotated position. CONCLUSIONS The biceps load test II is an effective diagnostic test for SLAP lesions.
Collapse
|
|
24 |
155 |
18
|
Aletaha D, Landewe R, Karonitsch T, Bathon J, Boers M, Bombardier C, Bombardieri S, Choi H, Combe B, Dougados M, Emery P, Gomez-Reino J, Keystone E, Koch G, Kvien TK, Martin-Mola E, Matucci-Cerinic M, Michaud K, O'Dell J, Paulus H, Pincus T, Richards P, Simon L, Siegel J, Smolen JS, Sokka T, Strand V, Tugwell P, van der Heijde D, van Riel P, Vlad S, van Vollenhoven R, Ward M, Weinblatt M, Wells G, White B, Wolfe F, Zhang B, Zink A, Felson D. Reporting disease activity in clinical trials of patients with rheumatoid arthritis: EULAR/ACR collaborative recommendations. ACTA ACUST UNITED AC 2008; 59:1371-7. [PMID: 18821648 DOI: 10.1002/art.24123] [Citation(s) in RCA: 154] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
|
17 |
154 |
19
|
Aletaha D, Landewe R, Karonitsch T, Bathon J, Boers M, Bombardier C, Bombardieri S, Choi H, Combe B, Dougados M, Emery P, Gomez-Reino J, Keystone E, Koch G, Kvien TK, Martin-Mola E, Matucci-Cerinic M, Michaud K, O'Dell J, Paulus H, Pincus T, Richards P, Simon L, Siegel J, Smolen JS, Sokka T, Strand V, Tugwell P, van der Heijde D, van Riel P, Vlad S, van Vollenhoven R, Ward M, Weinblatt M, Wells G, White B, Wolfe F, Zhang B, Zink A, Felson D. Reporting disease activity in clinical trials of patients with rheumatoid arthritis: EULAR/ACR collaborative recommendations. Ann Rheum Dis 2008; 67:1360-4. [PMID: 18791055 DOI: 10.1136/ard.2008.091454] [Citation(s) in RCA: 136] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
OBJECTIVE To make recommendations on how to report disease activity in clinical trials of rheumatoid arthritis (RA) endorsed by the European League Against Rheumatism (EULAR) and the American College of Rheumatology (ACR). METHODS The project followed the EULAR standardised operating procedures, which use a three-step approach: (1) expert-based definition of relevant research questions (November 2006); (2) systematic literature search (November 2006 to May 2007); and (3) expert consensus on recommendations based on the literature search results (May 2007). In addition, since this is the first joint EULAR/ACR publication on recommendations, an extra step included a meeting with an ACR panel to approve the recommendations elaborated by the expert group (August 2007). RESULTS Eleven relevant questions were identified for the literature search. Based on the evidence from the literature the expert panel recommended that each trial should report the following items: (1) disease activity response and disease activity states; (2) appropriate descriptive statistics of the baseline, the endpoints and change of the single variables included in the core set; (3) baseline disease activity levels (in general); (4) the percentage of patients achieving a low disease activity state and remission; (5) time to onset of the primary outcome; (6) sustainability of the primary outcome; (7) fatigue. CONCLUSIONS These recommendations endorsed by EULAR and ACR will help harmonise the presentations of results from clinical trials. Adherence to these recommendations will provide the readership of clinical trials with more details of important outcomes, while the higher level of homogeneity may facilitate the comparison of outcomes across different trials and pooling of trial results, such as in meta-analyses.
Collapse
|
Consensus Development Conference |
17 |
136 |
20
|
Nagai H, Guo J, Choi H, Kurup V. Interferon-gamma and tumor necrosis factor-alpha protect mice from invasive aspergillosis. J Infect Dis 1995; 172:1554-60. [PMID: 7594716 DOI: 10.1093/infdis/172.6.1554] [Citation(s) in RCA: 134] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The immunopathogenesis of invasive aspergillosis and the role played by cytokines are not fully understood. The roles of interferon (IFN)-gamma and tumor necrosis factor (TNF)-alpha were investigated in BALB/c mice infected intravenously with 5 x 10(5) Aspergillus fumigatus conidia. Eight groups of animals were studied, including 2 control groups (mice only infected with A. fumigatus and those given cortisone acetate and infected with A. fumigatus) and 6 groups of infected mice either treated or not treated with cortisone acetate and given IFN-gamma, anti-IFN-gamma, TNF-alpha, or anti-TNF-alpha. No deaths occurred among the mice treated with IFN-gamma and TNF-alpha, compared with 40%-80% mortality in the other groups. IFN-gamma- and TNF-alpha-treated mice also had fewer organs from which A. fumigatus could be cultured or demonstrated on histologic examination. These observations suggest that IFN-gamma and TNF-alpha have protective roles in invasive aspergillosis.
Collapse
|
|
30 |
134 |
21
|
Kim HA, Kim S, Seo YI, Choi HJ, Seong SC, Song YW, Hunter D, Zhang Y. The epidemiology of total knee replacement in South Korea: national registry data. Rheumatology (Oxford) 2008; 47:88-91. [PMID: 18077497 DOI: 10.1093/rheumatology/kem308] [Citation(s) in RCA: 126] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
OBJECTIVE Knee osteoarthritis (OA) is prevalent among the elderly in Asian countries; however, the utilization of total knee replacement (TKR) is unknown. Using data from a national registry, we sought to estimate the incidence of TKR by age and sex, and the trend for TKR utilization from 2002 to 2005 in South Korea. METHODS Reimbursement records from all hospitals in South Korea were extracted from the Health Insurance Review Agency (HIRA) database. Records with both the procedure code corresponding to a TKR and the diagnosis code of knee OA were selected. We estimated the age- and sex-specific rates of TKR. To compare the rate of TKR between men and women, we calculated age-standardized risk ratios. A TKR registry from a single centre containing more clinical information was analysed, and the differences in the clinical features between men and women were compared. RESULTS From 2002 to 2005, 47 961 TKRs were performed in subjects over the age of 40 yrs due to OA. The rate of TKR has increased over the 4 yrs and was much higher in women than in men. Compared with men, the age-standardized rate ratios for TKR in women ranged from 7.4 to 8.0. The single-centre registry data revealed that there was no difference in age, disease duration and the Kellgren-Lawrence grade at the time of surgery between men and women. CONCLUSION Using a national database, we found that the rate of TKR increased steadily from 2002 to 2005 in South Korea. The TKR rate in women was much higher than that in men. Risk factors that account for such disparity in TKR utilization need to be further investigated.
Collapse
|
Research Support, Non-U.S. Gov't |
17 |
126 |
22
|
Poole AR, Pidoux I, Reiner A, Choi H, Rosenberg LC. Association of an extracellular protein (chondrocalcin) with the calcification of cartilage in endochondral bone formation. J Cell Biol 1984; 98:54-65. [PMID: 6368573 PMCID: PMC2113002 DOI: 10.1083/jcb.98.1.54] [Citation(s) in RCA: 121] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
We examined bovine fetal epiphyseal and growth plate cartilages by immunofluorescence microscopy and immunoelectron microscopy using monospecific antibodies to a newly discovered cartilage-matrix calcium-binding protein that we now call chondrocalcin. Chondrocalcin was evenly distributed at relatively low concentration in resting fetal epiphyseal cartilage. In growth plate cartilage, it was absent from the extracellular matrix in the zone of proliferating chondrocytes but was present in intracellular vacuoles in proliferating, maturing and upper hypertrophic chondrocytes. The protein then disappeared from the lower hypertrophic chondrocytes and appeared in the adjoining extracellular matrix, where it was selectively concentrated in the longitudinal septa in precisely the same location where amorphous mineral was deposited in large amounts as demonstrated by von Kossa staining and electron microscopy. Mineral then spread out from these "nucleation sites" to occupy much of the surrounding matrix. Matrix vesicles were identified in this calcifying matrix but they bore no observable morphological relationship to these major sites of calcification where chondrocalcin was concentrated. Since chondrocalcin is a calcium-binding protein and has a strong affinity for hydroxyapatite, these observations suggest that chondrocalcin may play a fundamental role in the creation of nucleation sites for the calcification of cartilage matrix in endochondral bone formation.
Collapse
|
research-article |
41 |
121 |
23
|
Choi HJ, Hyun MS, Jung GJ, Kim SS, Hong SH. Tumor angiogenesis as a prognostic predictor in colorectal carcinoma with special reference to mode of metastasis and recurrence. Oncology 1998; 55:575-81. [PMID: 9778626 DOI: 10.1159/000011915] [Citation(s) in RCA: 118] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Tumor angiogenesis has proved to be a useful prognostic determinant for patients with various solid tumors. In this study, we investigated the quantitative expression of angiogenesis in colorectal carcinoma to determine how angiogenesis correlates with clinicopathologic factors and prognosis. One hundred twenty-seven specimens resected from patients with primary colorectal carcinoma were investigated immunohistochemically using a polyclonal antibody against factor-VIII-related antigen, and areas with the highest vascular density at the invasive tumor margin were counted at 200 times magnification. The microvessel count, defined as angiogenesis density (AD), became significantly higher with increase in histologic grade (p = 0.02) and Dukes stage (p = 0.001). AD was also significantly higher in patients with lymph node metastasis (p = 0. 005), lymphatic invasion (p = 0.042), vascular invasion (p < 0.001), and liver metastasis (p = 0.0004) than in those without. In addition, patients with synchronous distant hematogenous metastasis in stage D disease showed significantly higher AD than patients with nonhematogenous metastasis (p = 0.006). When 27 cases of disease recurrence after surgical resection with curative intent were stratified according to mode of spread, AD in cases with a hematogenous pattern of relapse proved to be significantly higher than in cases with nonhematogenous spread (p < 0.001). No significant differences were, however, found in AD when they were subdivided as to operative nodal status (p = 0.39 and 0.08 in the node-negative and the node-positive group, respectively). Multivariate analysis indicated that AD was an independent prognostic factor (p = 0.0004) in colorectal carcinoma. Quantitative evaluation of tumor angiogenesis at the invasive tumor margin is suggested to be a good prognostic indicator and a useful predictor for hematogenous spread and recurrence in patients with colorectal carcinoma.
Collapse
|
|
27 |
118 |
24
|
Izquierdo LA, Barros DM, Ardenghi PG, Pereira P, Rodrigues C, Choi H, Medina JH, Izquierdo I. Different hippocampal molecular requirements for short- and long-term retrieval of one-trial avoidance learning. Behav Brain Res 2000; 111:93-8. [PMID: 10840135 DOI: 10.1016/s0166-4328(00)00137-6] [Citation(s) in RCA: 115] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Rats were trained in one-trial step-down inhibitory avoidance and tested either 3 h or 31 days later. Ten minutes prior to the retention test, through indwelling cannulae placed in the CA1 region of the dorsal hippocampus, they received 0.5 microl infusions of: saline, a vehicle (2% dimethylsulfoxide in saline), the glutamate NMDA receptor blocker, aminophosphonopentanoic acid (AP5) (5.0 microg), the AMPA/kainate receptor blocker, cyanonitroquinoxaline dione (CNQX) (0.25 or 1.25 microg), the metabotropic receptor antagonist, methylcarboxyphenylglycine (MCPG) (0.5 or 2.5 microg), the inhibitor of calcium/calmodulin-dependent protein kinase II (KN62) (3.5 microg), the inhibitor of cAMP-dependent protein kinase (PKA), Rp-cAMPs (0.1 or 0.5 microg), the stimulant of the same enzyme, Sp-cAMPs (0.1 or 0.5 microg), or the inhibitor of the mitogen-activated protein kinase (MAPK) kinase, PD098059 (10 or 50 microM). CNQX, KN62 and PD098059 were dissolved in the vehicle; the other drugs were dissolved in saline. All these drugs, at the same doses, had been previously found to affect short- and long-term memory formation of this task. Retrieval measured 3 h after training (short-term memory) was blocked by CNQX and MCPG, and was unaffected by all the other drugs. In contrast, retrieval measured at 31 days was blocked by MCPG, Rp-cAMPs and PD098059, enhanced by Sp-cAMPs, and unaffected by CNQX, AP5 or KN62. The results indicate that, in CA1, glutamate metabotropic receptors are necessary for the retrieval of both short- and long-term memory; AMPA/kainate receptors are necessary for short-term but not long-term memory retrieval, and NMDA receptors are uninvolved in retrieval. Both the PKA and MAPK signalling pathways are required for the retrieval of long-term but not short-term memory.
Collapse
|
|
25 |
115 |
25
|
Kim WS, Kim MM, Choi HJ, Yoon SS, Lee MH, Park K, Park CH, Kang WK. Phase II study of high-dose lovastatin in patients with advanced gastric adenocarcinoma. Invest New Drugs 2001; 19:81-3. [PMID: 11291836 DOI: 10.1023/a:1006481423298] [Citation(s) in RCA: 108] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Lovastatin, an inhibitor of mevalonate synthesis, demonstrated in vitro antitumor activity against a variety of human cancer cells, especially in gastric adenocarcinoma cells at pharmacologically achievable concentrations. To determine the antitumor activity of this drug in advanced measurable gastric adenocarcinoma as well as to assess the toxicities and the pharmacokinetic features, we carried out a phase II study of high-dose lovastatin. Patients received lovastatin 35 mg/kg/day for 7 consecutive days, with ubiquinone (60 mg qid p.o.) to prevent rhabdomyolysis. The treatment was repeated every 28 days. From March 1996 to January 1997, 16 patients (median age, 57 years; range, 34-68) were entered into the study, 14 of whom were evaluated for response and toxicity. No patient achieved a response. A total of 28 cycles were administered. The median number of cycles was 2 (range, 1 to 4). Anorexia was the most common toxicity (64%), but decreased oral intake was observed only in 3 cycles. Two patients developed myalgia with elevated muscle enzyme. When used in this dosage and schedule, lovastatin does not appear to be effective for patients with advanced gastric adenocarcinoma.
Collapse
|
Clinical Trial |
24 |
108 |