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Kwon HJ, Sung BK, Kim JW, Lee JH, Kim ND, Yoo MA, Kang HS, Baek HS, Bae SJ, Choi JS, Takahashi R, Goto S, Chung HY. The effect of lipopolysaccharide on enhanced inflammatory process with age: Modulation of NF-κB. J Am Aging Assoc 2013; 24:163-71. [PMID: 23604881 DOI: 10.1007/s11357-001-0017-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Oxidative stress is thought to be a causative factor for age-related damage in a wide variety of cellular constituents that can lead to dysfunction and various pathological conditions, including the inflammatory process. At the molecular level, the redox-sensitive transcription factor, NF-κB plays a key role in the regulation of the inflammatory process, along with cytokines, cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS). We studied the mechanism underlying the modulation of the inflammatory reaction with age by investigating NF-κB activation and the expression of COX-2, iNOS, and cytokines genes in hepatic tissues isolated from young and old rats. We expanded our investigation of these factors in rats injected with the inflammatory activator, lipopolysaccharide (LPS). Data showed that NF-κB activity was up-regulated with age and was further enhanced by LPS injection, indicating an increased susceptibility and sensitivity to the inflammatory stimulus with age. To explore further the molecular events leading to NF-κB activation, we investigated the inhibitory component of NF-κB complex, IκB. Cytosolic IκBα, but not IκBβ, was significantly decreased in both old and LPS-treated rats, signifying the enhanced migration of cytosolic NF-κB complex into the nucleus following dissociation from the inhibitor. The appearance of the polypeptide, p65, as determined in the nucleus, corresponded with the change in IκBα, providing further supporting evidence for the molecular process involved in NF-κB activation. Our additional investigation of two proinflammatory-related enzymes, COX-2 and iNOS, and three cytokines, interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α, clearly showed aged-related increases, in corroboration with the NF-κB activation. Our results demonstrated that LPS injection caused the enhanced gene expression of inducible proinflammatory proteins, COX-2 and iNOS through NF-κB activation.
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Park HJ, Kim SS, Lee SY, Park NH, Chung EC, Rho MH, Kwon HJ, Kook SH. A practical MRI grading system for cervical foraminal stenosis based on oblique sagittal images. Br J Radiol 2013; 86:20120515. [PMID: 23410800 DOI: 10.1259/bjr.20120515] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE To propose a new and practical MRI grading method for cervical neural foraminal stenosis and to evaluate its reproducibility. METHODS We evaluated 50 patients (37 males and 13 females, mean age 49 years) who visited our institution and underwent oblique sagittal MRI of the cervical spine. A total of 300 foramina and corresponding nerve roots in 50 patients were qualitatively analysed from C4-5 to C6-7. We assessed the grade of cervical foraminal stenosis at the maximal narrowing point according to the new grading system based on T2 weighted oblique sagittal images. The incidence of each of the neural foraminal stenosis grades according to the cervical level was analysed by χ(2) tests. Intra- and interobserver agreements between two radiologists were analysed using kappa statistics. Kappa value interpretations were poor (κ<0.1), slight (0.1≤κ≤0.2), fair (0.2<κ≤0.4), moderate (0.4<κ≤0.6), substantial (0.6<κ≤0.8) and almost perfect (0.8<κ≤1.0). RESULTS Significant stenoses (Grades 2 and 3) were rarely found at the C4-5 level. The incidence of Grade 3 at the C5-6 level was higher than that at other levels, a difference that was statistically significant. The overall intra-observer agreement according to the cervical level was almost perfect. The agreement at each level was almost perfect, except for only substantial agreement at the right C6-7 by Reader 2. No statistically significant differences were seen according to the cervical level. Overall kappa values of interobserver agreement according to the cervical level were almost perfect. In addition, the agreement of each level was almost perfect. Overall intra- and interobserver agreement for the presence of foraminal stenosis (Grade 0 vs Grades 1, 2 and 3) and for significant stenosis (Grades 0 and 1 vs Grades 2 and 3) showed similar results and were almost perfect. However, only substantial agreement was seen in the right C6-7. CONCLUSION A new grading system for cervical foraminal stenosis based on oblique sagittal MRI provides reliable assessment and good reproducibility. This new grading system is a useful and easy method for the objective evaluation of cervical neural foraminal stenosis by radiologists and clinicians. ADVANCES IN KNOWLEDGE The use of the new grading system for cervical foraminal stenosis based on oblique sagittal MRI can be a useful method for evaluating cervical neural foraminal stenosis.
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Han JY, Cho JH, Kwon HJ, Nam KJ. Predicting portal hypertension as assessed by acoustic radiation force impulse: correlations with the Doppler ultrasound. Br J Radiol 2012; 85:e404-9. [PMID: 22815421 DOI: 10.1259/bjr/74648924] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
OBJECTIVE The purpose of this study was to assess the value of acoustic radiation force impulse (ARFI) for evaluating portal hypertension by correlating the elasticity of liver cirrhosis, as measured by ARFI, with haemodynamic indices measured by Doppler ultrasound. METHODS We evaluated the data of a total of 154 prospectively enrolled patients who underwent both duplex Doppler ultrasound and ARFI imaging. The duplex Doppler ultrasound indices, including the mean portal vein velocity, splenic index (SI) and splenoportal index (SPI) were evaluated to determine the statistical correlation with shear wave velocity (SWV) of ARFI. We also analysed the differences in the correlations between the SI, SPI and SWV of the group who had varices. The correlations were assessed with Spearman's rank correlation coefficients. RESULTS There was an increase of SWV in parallel with the increase of the SI (ρ=0.409, p<0.01) and SPI (ρ=0.451, p<0.01). In the patient group who did not have varices (n=74), the Doppler indices were found to be more correlated with the SWV (SI: ρ=0.447, SPI: ρ=0.552, p<0.01). However, the group with varices showed no correlation between the SWV and the Doppler parameters. CONCLUSION SWV of ARFI was well correlated statistically with Doppler parameters, but is of limited value in predicting portal hypertension directly owing to great variability of Doppler parameters. By evaluating the correlation between ARFI and Doppler ultrasound, we suggest that the SWV might be a non-invasive supplementary tool for predicting portal hypertension.
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Kwon HJ, Jin SC. Spontaneous healing of iatrogenic direct carotid cavernous fistula. Interv Neuroradiol 2012; 18:187-90. [PMID: 22681734 DOI: 10.1177/159101991201800210] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2011] [Accepted: 01/08/2012] [Indexed: 11/15/2022] Open
Abstract
Direct carotid-cavernous fistula (CCF) by selective navigation using a microcatheter or microwire is a rare complication, and its timing of treatment has not been elucidated. We report two cases of direct CCFs resulting from injury to the cavernous posterior segment of the internal carotid artery during selective navigation. We did not plan to perform emergent endovascular treatment for these direct CCFs because no symptoms related to direct CCFs developed. Follow-up angiography revealed spontaneous healing of both direct CCFs. Close observation rather than emergent treatment may represent another option for direct CCF by selective navigation during the endovascular procedure.
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Park SY, Kwon HJ, Choi Y, Lee HE, Kim SW, Kim JH, Kim IA, Jung N, Cho NY, Kang GH. P1-05-04: Distinct Patterns of Promoter CpG Island Methylation of Breast Cancer Subtype Are Associated with Different Stem Cell Phenotype. Cancer Res 2011. [DOI: 10.1158/0008-5472.sabcs11-p1-05-04] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Although DNA methylation profiles in breast cancer have been connected to breast cancer molecular subtype, there have been no studies of the association of DNA methylation with stem cell phenotype. This study was designed to evaluate promoter CpG islands methylation of 15 genes with regard to breast cancer subtype and to investigate whether the patterns of CpG island methylation in each subtype are associated with cancer stem cell phenotype represented by CD44+/CD24- or ALDH1 expression.
Methods: We performed MethyLight analysis for the methylation status of 15 promoter CpG island loci involved in breast cancer progression (APC, DLEC1, GRIN2B, GSTP1, HOXA1, HOXA10, IGF2, MT1G, RARB, RASSF1A, RUNX3, SCGB3A1, SFRP1, SFRP4, and TMEFF2) and determined cancer stem cell phenotype by CD44/CD24 and ALDH1 immunohistochmeistry in 36 luminal A, 33 luminal B, 30 luminal-HER2, 40 HER2 enriched, and 40 basal-like subtypes of breast cancer.
Results: The number of CpG island loci methylated was significantly different among subtypes and it was highest in luminal-HER2 subtype and lowest in basal-like subtype. Methylation frequencies and levels in 12 out of the 15 genes were significantly different among all subtypes and basal-like subtype showed significantly lower methylation frequencies and levels in nine genes, compared to luminal A, luminal B, HER2 enriched, and luminal-HER2 subtypes. CD44+/CD24- or ALDH1+ putative stem cell populations were most enriched in basal-like subtype. The methylation of promoter CpG islands was significantly lower in CD44+/CD24-cell (+) tumors, compared to CD44+/CD24-cell (−) tumors, even within the basal-like subtype. ALDH1 (+) tumors also had significantly lower methylation, compared to ALDH1 (−) tumors.
Conclusions: Our findings showed that promoter CpG island methylation was significantly different according to breast cancer subtype and stem cell phenotype of tumor, suggesting that breast cancers have different methylation patterns according to molecular subtypes and it is associated with stem cell phenotypes of the tumor.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-05-04.
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Park YH, Kwon HJ. Awake embolization of sigmoid sinus diverticulum causing pulsatile tinnitus: simultaneous confirmative diagnosis and treatment. Interv Neuroradiol 2011; 17:376-9. [PMID: 22005703 DOI: 10.1177/159101991101700316] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2011] [Accepted: 06/03/2011] [Indexed: 11/17/2022] Open
Abstract
Sigmoid sinus diverticulum, a rare dural sinus anomaly, is regarded as one of the very rare causes of pulsatile tinnitus, and there have been only a few reports on their surgical or endovascular management. We describe a 31-year-old woman presenting with a three-year pulsatile tinnitus in her right ear. After finding the small bony defect in her right temporal bone on CT which was filled with contrast after enhancement, we confirmed the presence of sigmoid sinus diverticulum with the cerebral angiogram and embolized it with two detachable coils in awake status. Right after filling the two coils into the sac, thanks to her alert consciousness, she was able to refer the disappearance of her tinnitus. The operation was finished only with the detachment of the coils.
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Lee SY, Kwon HJ, Ahn HS, Seo KY, Kim EK, Kim TI. Comparison of patient outcomes after implantation of Visian toric implantable collamer lens and iris-fixated toric phakic intraocular lens. Eye (Lond) 2011; 25:1409-17. [PMID: 21852802 DOI: 10.1038/eye.2011.176] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
PURPOSE We compared visual and refractive outcomes after implantation of Visian toric implantable collamer lenses (toric ICLs) and iris-fixated toric pIOLs (toric Artisans). PATIENTS AND METHODS A comparative retrospective analysis was performed. Toric ICLs were implanted into 30 eyes of 18 patients, and toric Artisans into 31 eyes of 22 recipients. We measured the logarithms of the minimum angle of resolution of uncorrected visual acuity (logMAR UCVA), logMAR of best spectacle-corrected corrected VA (logMAR BSCVA), MR, SE, and astigmatism (by the power vector method) before surgery and 1, 3, and 6 months thereafter. Differences between patients receiving each type of lens were compared by using a mixed model of repeated measures. RESULTS Visual improvements were evident after operation in both groups. By comparing the attempted to the achieved SE values, we were able to confirm that correction of refractive error was similar in both groups. However, the logMAR UCVA was significantly higher in the toric ICL group at all postoperative time points. Although manifest cylinder power and astigmatism (calculated by using the power vector method) gradually decreased in the toric ICL group, cylinder power 1 month postoperatively increased from -2.62 to -2.75 D; astigmatism was also increased at this time in the toric Artisan group. CONCLUSION The two tested toric pIOLs were similar in terms of the ability to correct refractive error, as assessed 3 months postoperatively. However toric ICLs corrected astigmatism more rapidly and safely. Notably, the large difference in astigmatism level between the two groups 1 month postoperatively indicates that toric ICLs are more effective when used to correct astigmatism.
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Lee JW, Kwon HJ, Jang PS, Chung NG, Cho B, Jeong DC, Kang JH, Kim HK. Two children with differing outcomes after treatment for pulmonary tuberculosis diagnosed after allogeneic hematopoietic stem cell transplantation. Transpl Infect Dis 2011; 13:520-3. [PMID: 21504530 DOI: 10.1111/j.1399-3062.2011.00641.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Tuberculosis (TB) is a rare infectious complication after hematopoietic stem cell transplantation (HSCT), but may be more significant in areas where the disease is endemic. Here, we present the clinical course of 2 children with acute lymphoblastic leukemia who were diagnosed with pulmonary TB after allogeneic HSCT. Both patients were treated for either probable or possible invasive fungal infection, as well as TB. One patient, diagnosed with TB 3 months after HSCT, showed remittent fever and symptoms that progressed to acute respiratory distress syndrome and death, despite 3 modifications to the anti-TB regimen. In contrast, another patient who was diagnosed with TB 8 months after transplantation, responded well to anti-TB medication and completed 1 year of treatment with resolution of lung lesions. Co-morbid opportunistic infections, profound host immunosuppression early after transplantation, and potential risk of multi-drug resistant-TB may act as major barriers to effective treatment of TB after HSCT despite appropriate anti-TB medication.
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Ryu HJ, Kim JE, Kim MJ, Kwon HJ, Suh SW, Song HK, Kang TC. The protective effects of interleukin-18 and interferon-γ on neuronal damages in the rat hippocampus following status epilepticus. Neuroscience 2010; 170:711-21. [PMID: 20674684 DOI: 10.1016/j.neuroscience.2010.07.048] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2010] [Revised: 07/22/2010] [Accepted: 07/22/2010] [Indexed: 12/27/2022]
Abstract
To elucidate whether interleukin-18 (IL-18) or interferon-γ (IFN-γ) participates in neurodegeneartion, we investigated the changes in IL-18 and IFN-γ systems within the rat hippocampus following status epilepticus (SE). In non-SE induced animals, IL-18, IL-18 receptor α (IL-18Rα), IFN-γ and IFN-γ receptor α (IFN-γRα) immunoreactivity was not detected in the hippocampus. Following SE, IL-18 immunoreactivity was increased in CA1-3 pyramidal cells as well as dentate granule cells. IL-18 immunoreactivity was also up-regulated in astrocytes and microglia/macrophages. IL-18Rα immunoreactivity was detected in astrocytes and microglia/macrophages. IFN-γ immunoreactivity was detected only in astrocytes within all regions of the hippocampus. IFN-γRα immunoreactivity was increased in neurons as well as astrocytes. Intracerebroventricular infusions of recombinant rat IL-18 or IFN-γ alleviated SE-induced neuronal damages, while neutralization of IL-18, IFN-γ or their receptors aggravated them, as compared to saline-infused animals. These findings suggest that astroglial-mediated IFN-γ pathway in response to IL-18 induction may play an important role in alleviation of SE-induced neuronal damages.
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Sasaki H, Muramatsu T, Kwon HJ, Yamamoto H, Hashimoto S, Jung HS, Shimono M. Down-regulated genes in mouse dental papillae and pulp. J Dent Res 2010; 89:679-83. [PMID: 20448247 DOI: 10.1177/0022034510366844] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Important factors involved in odontogenesis in mouse dental papillae disappear between the pre- and post-natal stages of development. Therefore, we hypothesized that certain genes involved in odontogenesis in dental papillae were subject to pre-/post-natal down-regulation. Our goal was to identify, by microarray analysis, which genes were down-regulated. Dental papillae were isolated from embryonic 16-day-, 18-day- (E16, E18), and post-natal 3-day-old (P3) murine first mandibular molar germs and analyzed by microarray. The number of down-regulated genes was 2269 between E16 and E18, and 3130 between E18 and P3. Drastic down-regulation (fold change > 10.0) of Adamts4, Aldha1a2, and Lef1 was observed at both E16 and E18, and quantitative RT-PCR revealed a post-natal reduction in their expression (Adamts4, 1/3; Aldh1a2, 1/13; and Lef1, 1/37). These results suggest that down-regulation of these three genes is an important factor in normal odontogenesis in dental papillae.
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Kim SH, Kwon HJ, Cho JH, Lee SW, Rha SH, Choi J, Nam KJ. Atypical radiological features of a leiomyosarcoma that arose from the ovarian vein and mimicked a vascular tumour. Br J Radiol 2010; 83:e95-7. [PMID: 20418463 DOI: 10.1259/bjr/50917539] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Leiomyosarcomas of the ovarian vein are extremely rare tumours. Most tumours are hypervascular and typically have a large avascular centre of necrosis. We experienced a case of a retroperitoneal leiomyosarcoma that arose from the ovarian vein with marked vascular proliferation and dilatation within the tumour. To the best of our knowledge, this is the first case report of a retroperitoneal leiomyosarcoma with an atypical vascular structure in the clinical literature.
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Hong IS, Park BS, Jang JH, Kwon HJ, Cho YS, Hwang YS. Design and construction of a compact microwave proton source for a proton linac. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2010; 81:02A314. [PMID: 20192335 DOI: 10.1063/1.3271170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A 100 MeV, 20 mA proton linear accelerator is being developed by the Proton Engineering Frontier Project at the Korea Atomic Energy Research Institute. 20 MeV acceleration system using radio frequency quadrupole and drift tube linac was already developed and has been tested. To operate this acceleration system with a long time, more reliable proton source is needed. A compact microwave proton source was proposed and has been designed and constructed as a prototype ion source for the 100 MeV proton linear accelerator. The design of microwave power injection system is based on the microwave proton injector at LANL and CEA. The wave power from a 2.45 GHz, 2 kW magnetron source is introduced into a compact plasma chamber with 7 cm diameter and 5 cm length through a standard tapered, double-ridged waveguide (WRD250) and a quartz window. The microwave power supply is installed on high voltage platform. Axial magnetic fields up to 1 kG can be provided with a water-cooled solenoid coil. A single-hole three electrode extraction system is designed for an extraction current up to 30 mA at a 50 kV extraction voltage. The design and initial operations of the proton source are presented.
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Park HW, Wang JH, Kim JU, Koo SW, Kwon HJ, Jang YJ. Does isoflurane enhance rhinovirus replication and virus-induced cytokine secretion in airway epithelial cells? Acta Anaesthesiol Scand 2008; 52:1046-50. [PMID: 18840102 DOI: 10.1111/j.1399-6576.2008.01691.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND There have been no previous studies regarding the effect of volatile anesthetics on human rhinovirus (RV) infection in airway epithelial cells of patients with an upper respiratory infection (URI). We have therefore evaluated in vitro the effect of isoflurane on RV infection in airway epithelial cells. METHODS A549 cells and RV-infected A549 cells were treated with isoflurane for 2 or 4 h. Surface expression of intercellular adhesion molecule-1 (ICAM-1) was assessed by flow cytometry, and effects on the secretion of interleukin (IL)-6 and IL-8 were measured by ELISA. The effect on RV replication in the cells was determined by viral titer. RESULTS Isoflurane treatment for 2 or 4 h had no significant effect on ICAM-1 expression and secretion of IL-6 and IL-8 in control cells. Isoflurane also had no significant additional effect on RV-induced ICAM-1 expression and secretion of IL-6 and IL-8. Viral titers were not significantly influenced by isoflurane. CONCLUSION Isoflurane treatment showed no additional effects with RV on ICAM-1 expression, secretion of IL-6 and IL-8, and viral titer in A549 cells. These results suggest that isoflurane itself may not increase further RV infections, inflammations, and viral replication in patients with a viral URI.
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Kwon S, Kang DM, Kim SY, Sa KJ, Lee CG, Lim JH, Jee YK, Ha MN, Hong SJ, Hong YC, Kwon HJ, Oh SY. Dietary factors in relation to atopic dermatitis among urban school‐aged children in Korea. FASEB J 2008. [DOI: 10.1096/fasebj.22.1_supplement.876.5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Kwon HJ, Lee JY, Cho BK, Park HJ. Menstrual irregularity during isotretinoin treatment. J Eur Acad Dermatol Venereol 2006; 21:562-3. [PMID: 17374003 DOI: 10.1111/j.1468-3083.2006.01961.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Rajkarnikar A, Kwon HJ, Ryu YW, Suh JW. Catalytic Domain of AfsKav Modulates Both Secondary Metabolism and Morphologic Differentiation in Streptomyces avermitilis ATCC 31272. Curr Microbiol 2006; 53:204-8. [PMID: 16874544 DOI: 10.1007/s00284-006-0062-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2006] [Accepted: 05/11/2006] [Indexed: 11/30/2022]
Abstract
Genetic characterization of afsK-av (SAV3816) in Streptomyces avermitilis ATCC 31272 was performed to evaluate the role(s) of this eukaryotic-type serine-threonine protein kinase (STPK) in the regulation of morphologic differentiation and secondary metabolism. The afsK-av::neo mutant (SJW4001) was defective in sporulation, melanogenesis, and avermectin production. These phenotypic defects were complemented by introduction of either the intact afsK-av or the 900-nt catalytic domain region. The catalytic domain restored sporulation and melanogenesis to SJW4001 whereas it partially recovered avermectin production. This study reveals that AfsKav is a pleiotropic regulator and demonstrates in vivo that the C-region of AfsKav is not essential for its regulatory role in S. avermitilis differentiations.
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Kwon HJ, Hong YK, Kim KH, Han CH, Cho SH, Choi JS, Kim BW. Methanolic extract of Pterocarpus santalinus induces apoptosis in HeLa cells. JOURNAL OF ETHNOPHARMACOLOGY 2006; 105:229-34. [PMID: 16326057 DOI: 10.1016/j.jep.2005.10.025] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2005] [Revised: 10/25/2005] [Accepted: 10/26/2005] [Indexed: 05/05/2023]
Abstract
Ptercarpus santalinus (Fabaceae) has been used as a folk remedy in Korea, and it has been shown to exhibit antiinflammations, antiulcers and anticancer effects. In this study, therefore, we report the cytotoxic activity and the mechanism of cell death exhibited by the methanol extract of Ptercarpus santalinus (MEPS) against human cervical adenocarcinoma cell line, HeLa. Treatment of HeLa cells with various concentrations of MEPS resulted in growth inhibition and induction of apoptosis in a dose-dependent manner as determined by cell viability, chromatin condensation, DNA fragmentation and sub-G1 phase accumulation. In Western blot analysis, apoptosis in the HeLa cells was associated with the release of cytochrome C from mitochondria into the cytosol, activation of caspases-3, -8, -9 and proteolytic cleavage of PARP. These results suggest that MEPS exhibits antiproliferative effect on HeLa cells via apoptosis, and it may be a potential candidate in field of anticancer drug discovery.
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Abstract
Clarithromycin (CM) has been found to inhibit the production of the intercellular adhesion molecule (ICAM)-1 and the secretion of interleukin (IL)-6 and IL-8, which may have beneficial effects on the pathophysiological changes related to rhinovirus (RV) infection. The effect of CM on RV infection in A549 cells was therefore investigated. Cells were pre-treated with 1, 10 or 100 microM CM, either starting 3 days before infection and continuing thereafter, or by addition at the time of infection. RV titre, as measured by culture on Medical Research Council 5 cells, was reduced by CM, with the degree of reduction being greater when CM was added 3 days before infection than when it was added at the time of infection. CM treatment inhibited the RV-induced increase in ICAM-1 mRNA and protein, as well as the RV-induced secretion of IL-1beta, IL-6, and IL-8. These effects were greater in cells treated with 10 microM than in those treated with 100 microM CM, and the maximum effect was observed 3 days after viral infection. In contrast, secretion of IL-8 was not inhibited significantly when CM was added at the time of viral infection. The findings of this study suggest that, in A549 cells, clarithromycin inhibits the induction of intercellular adhesion molecule-1 expression, cytokine elaboration, and viral infection.
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Choi JH, Oh SW, Kang MS, Kwon HJ, Oh GT, Kim DY. Trichostatin A attenuates airway inflammation in mouse asthma model. Clin Exp Allergy 2005; 35:89-96. [PMID: 15649272 DOI: 10.1111/j.1365-2222.2004.02006.x] [Citation(s) in RCA: 146] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Histone deacetylase (HDAC) inhibition has been demonstrated to change the expression of a restricted set of cellular genes. T cells are essential in the pathogenesis of allergen-induced airway inflammation. It was recently reported that treatment with HDAC inhibitors induces a T cell-suppressive effect. OBJECTIVE The purpose of this study was to determine whether treatment with trichostatin A (TSA), a representative HDAC inhibitor, would reduce allergen-induced airway inflammation in a mouse asthma model. METHODS BALB/c mice were intraperitoneally sensitized to ovalbumin (OVA) and challenged with an aerosol of OVA. TSA (1 mg/kg body weight) was injected intraperitoneally every 2 days beginning on day 1. Mouse lungs were assayed immunohistochemically for HDAC1, a major HDAC subtype, and for infiltration of CD4+ cells. The effect of TSA on airway hyper-responsiveness (AHR) was determined, and the bronchoalveolar lavage fluid (BALF) of these mice was assayed for the number and types of inflammatory cells, and for the concentrations of IL-4, IL-5, and IgE. RESULTS HDAC1 was localized within most airway cells and infiltrating inflammatory cells of asthmatic lungs. Treatment with TSA significantly attenuated AHR, as well as the numbers of eosinophils and lymphocytes in BALF. TSA also reduced infiltration of CD4+ and inflammatory cells and mucus occlusions in lung tissue, and decreased the concentrations of IL-4, IL-5, and IgE in BALF. CONCLUSION TSA attenuated the development of allergic airway inflammation by decreasing expression of the Th2 cytokines, IL-4 and IL-5, and IgE, which resulted from reduced T cell infiltration. Our results suggest that HDAC inhibition may attenuate the development of asthma by a T cell suppressive effect.
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Lee KW, Lee Y, Kwon HJ, Kim DS. Sp1-associated activation of macrophage inflammatory protein-2 promoter by CpG-oligodeoxynucleotide and lipopolysaccharide. Cell Mol Life Sci 2005; 62:188-98. [PMID: 15666090 DOI: 10.1007/s00018-004-4399-y] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Macrophage inflammatory protein-2 (MIP-2) is a C-X-C chemokine that is important in recruiting neutrophils to inflammatory sites. Our previous reports demonstrated that lipopolysaccharide (LPS) or CpG-oligode-oxynucleotide (CpG-ODN) rapidly induce MIP-2 gene expression in the macrophage cell line, RAW 264.7. Here, we show that the DNA sequence of the MIP-2 promoter between -114 and +14 is sufficient for strong promoter activity in LPS- or CpG-ODN-stimulated RAW 264.7 cells. Importantly, comprehensive mutant analysis reveals that an Sp1 element in the promoter region between -114 and -94 is essential for synergistic MIP-2 promoter activation by NF-kappaB and c-Jun regardless of the presence of an AP-1 site. By combining deletion or site-specific mutant analysis with immunocomplex assays, we also confirmed that Sp1 mediates the recruitment of transcription factors NF- kappaB and c-Jun in LPS- or CpG-ODN-treated RAW 264.7 cells. Several lines of experimental evidence imply that the Sp1-binding element is an important determinant of MIP-2 promoter activity, and that NF-kappaB, c-Jun and Sp1 can functionally cooperate to elicit maximal activation of the promoter.
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Kwon HJ, Park JH, Jin GY, Chung MJ, Lim ST, Kim MH, Kim HJ, Lee YC. Posterior mediastinal paraganglioma with bilateral adrenal pheochromocytoma. Respir Med 2004; 98:574-6. [PMID: 15191044 DOI: 10.1016/j.rmed.2003.12.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Paraganglioma and adrenal pheochromocytoma are tumors of common origin arising from chromaffin cells. However, it is extremely rare to find mediastinal paraganglioma simultaneously with bilateral adrenal pheochromocytoma. We report a 53-year-old man who was diagnosed with posterior mediastinal paraganglioma and bilateral adrenal pheochromocytoma and who underwent successful excision of the posterior mediastinal mass and bilateral total adrenalectomy.
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Kim JC, Shin DH, Kim SH, Oh KS, Jung YH, Kwon HJ, Yun HI, Shin HC, Chung MK. Peri- and postnatal developmental toxicity of the fluoroquinolone antibacterial DW-116 in rats. Food Chem Toxicol 2004; 42:389-95. [PMID: 14871581 DOI: 10.1016/j.fct.2003.10.002] [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] [Received: 06/20/2003] [Accepted: 10/07/2003] [Indexed: 11/30/2022]
Abstract
DW-116 is a fluoroquinolone antibacterial developed by Dong-Wha Pharmaceutical Industry Co. The aim of this study is to determine the potential adverse effects of this chemical on pregnancy, delivery and lactation of dams and on peri- and postnatal development of F1 offspring. The test chemical was orally administered to pregnant rats from day 16 of pregnancy, through parturition and throughout the period of lactation up to weaning (postnatal day 21) at dose levels of 0, 10, 50, or 250 mg/kg/day. The progeny were examined at birth and subsequently to weaning. Mortality, body weight change, physical signs of postnatal development (pinna detachment, incisor eruption, fur development, eye opening, testis descent and vaginal opening) and behavioral function (righting reflex, negative geotaxis, grip-strength, pupillary reflex, acoustic startle response, rotating rod test, open field test and water-filled T-maze test) were evaluated. When the exposed offspring reached maturity (11 weeks old) their reproductive capacity was assessed. Maternal toxicity was observed only in the highest dose group and was limited to decreased food consumption during the late stage of pregnancy. However, this change was not observed during the lactation period. There were no adverse effects on mortality, clinical signs, body weight, necropsy findings, organ weight of dams in any treatment group. No adverse effects on the offspring were seen with the low and middle doses tested, but the highest dose increased postnatal mortality. The number of stillborn was also increased at the highest dose but the difference was not statistically significant. Meanwhile, no treatment-related effects were observed in clinical sign, developmental and behavioral landmarks and necropsy findings at any dose levels tested. There were no treatment-related effects on the mating of the F1 generation and resulting F2 offspring. The results of this study indicate that the peri- and postnatal administration of DW-116 to female rats results in an increase in postnatal mortality at a minimally maternotoxic dose, i.e., 250 mg/kg/day. Under the experimental conditions, the no-observed-adverse-effect level for peri- and postnatal developmental toxicity was considered to be 50 mg/kg/day.
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Emenius G, Pershagen G, Berglind N, Kwon HJ, Lewné M, Nordvall SL, Wickman M. NO2, as a marker of air pollution, and recurrent wheezing in children: a nested case-control study within the BAMSE birth cohort. Occup Environ Med 2003; 60:876-81. [PMID: 14573719 PMCID: PMC1740422 DOI: 10.1136/oem.60.11.876] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AIMS To investigate the association between air pollution, including with NO2, and recurrent wheezing during the first two years of life. METHODS A birth cohort (BAMSE) comprised 4089 children, for whom information on exposures, symptoms, and diseases was available from parental questionnaires at ages 2 months, and 1 and 2 years. NO2 was measured during four weeks in and outside the dwellings of children with recurrent wheezing and two age matched controls, in a nested case-control study (540 children). RESULTS Conditional logistic regression showed an OR of 1.60 (95% CI 0.78 to 3.26) among children in the highest quartile of outdoor NO2 exposure in relation to those in the lowest quartile, adjusted for potential confounders. The corresponding OR for indoor NO2 was 1.51 (95% CI 0.81 to 2.82). An interaction with environmental tobacco smoke (ETS) was indicated with an OR of 3.10 (95% CI 1.32 to 7.30) among children exposed to the highest quartile of indoor NO2 and ETS. The association between NO2 and recurrent wheezing appeared stronger in children who did not fulfil the criteria for recurrent wheezing until their second year. CONCLUSIONS Although the odds of increased recurrent wheezing are not statistically significantly different from one, results suggest that exposure to air pollution including NO2, particularly in combination with exposure to ETS, increases the risk of recurrent wheezing in children.
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Choi JH, Kwon HJ, Yoon BI, Kim JH, Han SU, Joo HJ, Kim DY. Expression profile of histone deacetylase 1 in gastric cancer tissues. Jpn J Cancer Res 2001; 92:1300-4. [PMID: 11749695 PMCID: PMC5926683 DOI: 10.1111/j.1349-7006.2001.tb02153.x] [Citation(s) in RCA: 259] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Although histone deacetylases (HDACs) appear to play a crucial role in carcinogenesis, the expression status of HDACs in primary human cancer tissues has not yet been reported. In this study, we investigated the expression level of HDAC1 in 25 paired primary human gastric cancer (GC) tissues and corresponding normal tissues through semi-quantitative RT-PCR and immunoblot analysis. The HDAC1 expression pattern was also topologically examined through immunohistochemistry. Overexpression of HDAC1 mRNA was detected in 68% of GC tissues (17 of 25), and the relative density of HDAC1 mRNA in GC tissue was increased 1.8-fold versus the normal counterpart (P < 0.01). Elevated expression of HDAC1 protein was also detected in 61% of GC samples (11 of 18), which also showed an increased mRNA level of HDAC. Immunohistochemically, overexpression of HDAC1 was predominantly localized in the nuclei of most neoplastic cells, including embolic tumor cells, whereas normal glandular epithelial cells revealed only weak HDAC1 expression that was focal in distribution. Thus, the present study clearly demonstrates that HDAC1 is overexpressed in GC and probably plays a significant role in gastric carcinogenesis.
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Amada K, Kwon HJ, Haruki M, Morikawa M, Kanaya S. Ca(2+)-induced folding of a family I.3 lipase with repetitive Ca(2+) binding motifs at the C-terminus. FEBS Lett 2001; 509:17-21. [PMID: 11734198 DOI: 10.1016/s0014-5793(01)03108-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
In order to understand a role of the Ca(2+) ion on the structure and function of a Ca(2+)-dependent family I.3 lipase from Pseudomonas sp. MIS38, apo-PML, holo-PML, holo-PML*, and the N-terminal domain alone (N-fragment) were prepared and biochemically characterized. Apo-PML and holo-PML represent refolded proteins in the absence and presence of the Ca(2+) ion, respectively. Holo-PML* represents a holo-PML dialyzed against 20 mM Tris-HCl (pH 7.5). The results suggest that the C-terminal domain of PML is almost fully unfolded in the apo-form and its folding is induced by Ca(2+) binding. The folding of this C-terminal domain may be required to make a conformation of the N-terminal catalytic domain functional.
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