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Noh JM, Park W, Suh CO, Keum KC, Kim YB, Shin KH, Kim K, Chie EK, Ha SW, Kim SS, Ahn SD, Shin HS, Kim JH, Lee HS, Lee NK, Huh SJ, Choi DH. Is elective nodal irradiation beneficial in patients with pathologically negative lymph nodes after neoadjuvant chemotherapy and breast-conserving surgery for clinical stage II-III breast cancer? A multicentre retrospective study (KROG 12-05). Br J Cancer 2014; 110:1420-6. [PMID: 24481403 PMCID: PMC3960607 DOI: 10.1038/bjc.2014.26] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Revised: 12/29/2013] [Accepted: 01/08/2014] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND To evaluate the effects of elective nodal irradiation (ENI) in clinical stage II-III breast cancer patients with pathologically negative lymph nodes (LNs) (ypN0) after neoadjuvant chemotherapy (NAC) followed by breast-conserving surgery (BCS) and radiotherapy (RT). METHODS We retrospectively analysed 260 patients with ypN0 who received NAC followed by BCS and RT. Elective nodal irradiation was delivered to 136 (52.3%) patients. The effects of ENI on survival outcomes were evaluated. RESULTS After a median follow-up period of 66.2 months (range, 15.6-127.4 months), 26 patients (10.0%) developed disease recurrence. The 5-year locoregional recurrence-free survival and disease-free survival (DFS) for all patients were 95.5% and 90.5%, respectively. Pathologic T classification (0-is vs 1 vs 2-4) and the number of LNs sampled (<13 vs ≥13) were associated with DFS (P=0.0086 and 0.0012, respectively). There was no significant difference in survival outcomes according to ENI. Elective nodal irradiation also did not affect survival outcomes in any of the subgroups according to pathologic T classification or the number of LNs sampled. CONCLUSIONS ENI may be omitted in patients with ypN0 breast cancer after NAC and BCS. But until the results of the randomised trials are available, patients should be put on these trials.
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Lee NK, Kim S, Kim TU, Kim DU, Seo HI, Jeon TY. Diffusion-weighted MRI for differentiation of benign from malignant lesions in the gallbladder. Clin Radiol 2013; 69:e78-85. [PMID: 24290779 DOI: 10.1016/j.crad.2013.09.017] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Revised: 09/13/2013] [Accepted: 09/20/2013] [Indexed: 02/07/2023]
Abstract
AIM To investigate the value of diffusion-weighted imaging (DWI) for differentiating benign from malignant gallbladder lesions. MATERIALS AND METHODS One hundred and twenty-six patients who had undergone magnetic resonance imaging (MRI) with DWI, in whom the histopathological diagnosis of their gallbladder lesions was confirmed by biopsy or surgery were retrospectively analysed. Thirty-six malignant and 90 benign lesions were included. Two radiologists categorized gallbladder lesions into seven types on two imaging sets [T2-weighted imaging (WI) alone and combined T2WI and DWI (b = 800 s/mm(2))] according to the presence of wall thickening, layered patterns, morphology of the mass, and diffusion restriction. Disagreements were resolved in consensus. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of each imaging set for diagnosing gallbladder carcinoma were calculated. The diagnostic performance of each imaging set was calculated using receiver operating characteristic (ROC) curve analysis. Additionally, ADC values of malignant and benign gallbladder lesions were compared separately for 1.5 and 3 T MRI. RESULTS The sensitivity, specificity, PPV, and NPV of diagnosis at T2WI were 97.2%, 86.7%, 74.5%, and 98.7%, respectively. The sensitivity, specificity, PPV, and NPV using combined T2WI and DWI were 97.2%, 92.2%, 83.3%, and 98.8%, respectively. Diagnostic accuracy for gallbladder carcinoma slightly improved after adding DWI, from 0.92 to 0.95 (p < 0.05). ADC values for gallbladder carcinoma were significantly lower than those for benign lesions. Mean ADC values of malignant and benign lesions were 0.97 ± 0.25 × 10(-3) and 1.72 ± 0.56 × 10(-3) mm(2)/s, respectively, at 1.5 T (p < 0.001), and 1.04 ± 0.38 × 10(-3) and 2.2 ± 0.72 × 10(-3) mm(2)/s, respectively, at 3 T (p < 0.001). CONCLUSION DWI can improve diagnostic accuracy for differentiating benign from malignant gallbladder lesions.
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Lee NK, Son SM, Nam SH, Kwon JW, Kang KW, Kim K. Effects of progressive resistance training integrated with foot and ankle compression on spatiotemporal gait parameters of individuals with stroke. J Phys Ther Sci 2013; 25:1235-7. [PMID: 24259765 PMCID: PMC3820171 DOI: 10.1589/jpts.25.1235] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Accepted: 05/15/2013] [Indexed: 11/24/2022] Open
Abstract
[Purpose] The purpose of this study was to investigate the effect of progressive resistance training (PRT) integrated with foot and ankle compression on the gait ability of post-stroke patients. [Subjects and Methods] Participants were randomly allocated to two groups: the PRT group (n=14) and the control group (n=14). Subjects in the PRT group received training for 30 minutes, five days per week, for a period of six weeks. Gait ability was evaluated using the RsScan system. [Results] Use of PRT integrated with foot and ankle compression resulted in significant improvements in temporal parameters (gait velocity, step time, and double limb support) and spatial parameters (step length, stride length, and heel-to- heel base of support). [Conclusion] Progressive resistance training integrated with foot and ankle compression improved the gait ability of stroke patients. These results suggest the feasibility and suitability of integration of PRT with foot and ankle compression for individuals with stroke.
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Son SM, Kang KW, Lee NK, Nam SH, Kwon JW, Kim K. Influence of Isokinetic Strength Training of Unilateral Ankle on Ipsilateral One-legged Standing Balance of Adults. J Phys Ther Sci 2013; 25:1313-5. [PMID: 24259783 PMCID: PMC3820187 DOI: 10.1589/jpts.25.1313] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Accepted: 05/29/2013] [Indexed: 01/19/2023] Open
Abstract
[Purpose] The purpose of the current study was to investigate the changes in one-legged
standing balance of the ipsilateral lower limb following unilateral isokinetic strength
training. [Subjects and Methods] Thirty healthy adult volunteers were randomly assigned to
either a training group or a control group, so that each group included 15 subjects.
Subjects in the training group performed unilateral ankle isokinetic exercises of the
dominant leg using the Biodex 3 PRO System for a period of four weeks. Ipsilateral
one-legged standing balance was evaluated before and after the intervention with three
stability indexes of balance using the Biodex System: Anterior-Posterior Stability Index
(APSI), Medial-Lateral Stability Index (MLSI), and Overall Stability Index (OSI).
[Results] Comparison of pre- and post-test data revealed significant improvements in
strength values (dorsiflexion, plantarflexion, eversion, and inversion) and stability
indexes (APSI, MLSI, OSI). [Conclusion] These results suggest that ankle strengthening
exercise can be considered as a form of exercise that may assist individuals with
improvement of balance.
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Lee NK, Kwon JW, Son SM, Nam SH, Choi YW, Kim CS. Changes of plantar pressure distributions following open and closed kinetic chain exercise in patients with stroke. NeuroRehabilitation 2013; 32:385-90. [PMID: 23535803 DOI: 10.3233/nre-130859] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
OBJECTIVE The aim of this study is to investigate whether progressive resistive training with closed-kinetic chain (CKC) and open-kinetic chain (OKC) exercises could change plantar pressure distribution during walking in patients with stroke. METHODS Thirty-nine stroke patients were recruited and randomly divided into a CKC exercise group (n = 13), an OKC exercise group (n = 13), and a control group (n = 13). Both CKC and OKC exercise groups performed their own respective training programs 5 times per week for 6 weeks, whereas no training was done in the control group. Barefoot plantar pressure distribution was measured during walking in terms of contact area (CA), peak contact force (PCF), and contact impulse (CI) on each of three foot regions (i.e. forefoot (FF), midfoot (MF), and hindfoot (HF)). RESULTS In the CKC exercise group, there were significant changes in only the CA and PCF of HF. In the OKC exercise and control groups, no significant differences were found for all variables of plantar pressure distributions. CONCLUSION We found that resistive training with closed kinetic chain exercises could be an effective treatment method for improving normal gait patterns in stroke patients. These findings may be attributed to the fact that CKC exercise induced use of the ankle and knee muscles and provided repetitive sensory input from the affected foot.
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Kim TU, Kim S, Lee JW, Lee NK, Jeon TY, Park DY. MDCT features in the differentiation of T4a gastric cancer from less-advanced gastric cancer: significance of the hyperattenuating serosa sign. Br J Radiol 2013; 86:20130290. [PMID: 23873904 DOI: 10.1259/bjr.20130290] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
OBJECTIVE The purpose of our study was to evaluate CT findings to differentiate between T4a and less advanced gastric cancers. METHODS The institutional review board approved this study and waived informed consent. This study included 228 retrospectively identified patients with surgically confirmed gastric cancer (138 T1, 25 T2, 24 T3 and 41 T4a) and who had also undergone pre-operative CT scan. Transverse and multiplanar reconstruction scans were reviewed in consensus by two other blinded radiologists. The following CT findings that differentiate T4a from less advanced cancers were evaluated: nodular or an irregular outer layer of the gastric wall, haziness of the perigastric fat and a hyperattenuating serosa sign. The CT features of T4a and less advanced gastric cancers were compared by means of univariate and multivariate analyses. RESULTS In univariate analysis, nodular or an irregular outer layer of the gastric wall, haziness of the perigastric fat and the hyperattenuating serosa sign were significant in differentiation between T4a and less advanced gastric cancers. In addition, nodular or an irregular outer layer of the gastric wall and the hyperattenuating serosa sign were significant in differentiation between T3 and T4a. In multivariate logistic analysis, the hyperattenuating serosa sign was the most significant finding in differentiation between T3 and T4a (odds ratio, 4.210; 95% confidence intervals, 1.581-11.214; p=0.004). CONCLUSION The hyperattenuating serosa sign may be a useful CT finding in differentiation between T4a and less-advanced gastric cancers. ADVANCES IN KNOWLEDGE The hyperattenuating serosa sign is associated with gastric cancer with invading the serosa and can facilitate planning of the optimal pre-operative evaluation and treatment.
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Lee NK, Kwon YH, Son SM, Nam SH, Kim JS. The effects of aging on visuomotor coordination and proprioceptive function in the upper limb. J Phys Ther Sci 2013; 25:627-9. [PMID: 24259817 PMCID: PMC3804969 DOI: 10.1589/jpts.25.627] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Accepted: 01/11/2013] [Indexed: 11/24/2022] Open
Abstract
[Purpose] Sensorimotor processing, including motor performance, is altered during the process of normal aging. Previous studies have investigated tasks requiring complex visuomotor coordination and active joint reposition tests. Therefore, the purpose of this study was to investigate age-related changes in upper limb tasks, such as visuomotor coordination and proprioceptive acuity. [Subjects and Methods] We recruited 20 healthy elderly subjects and 20 healthy young subjects. We evaluated a tracking task for visuomotor function and a joint reposition test for integrity of proprioceptive sense in both hands of the elderly subjects, and compared the results with those of the healthy young subjects. [Results] The accuracy index scores for the tracking task were significantly lower in both the dominant and non-dominant hands of the elderly subjects than those of the young group. In addition, the reposition error score in the joint reposition test was significantly higher in the elderly group than in the young group. [Conclusion] Sensorimotor functions of both the dominant and non-dominant hands showed a decline in the elderly group. This finding suggests that sensorimotor function deteriorates with advancing age.
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Son SM, Kwon YH, Lee NK, Nam SH, Kim K. Deficits of Movement Accuracy and Proprioceptive Sense in the Ipsi-lesional Upper Limb of Patients with Hemiparetic Stroke. J Phys Ther Sci 2013; 25:567-9. [PMID: 24259803 PMCID: PMC3804967 DOI: 10.1589/jpts.25.567] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Accepted: 12/25/2012] [Indexed: 11/24/2022] Open
Abstract
[Purpose] Previous studies have reported on motor deficits in the ipsilateral upper
limbs (UL) of a damaged brain hemisphere in motor tasks. However, little is known about
sensory deficits on the ipsilateral side. Therefore, we investigated whether both motor
and sensory function of the ipsilateral UL are affected in patients with stroke. [Subjects
and Methods] Fifty patients with unilateral stroke and 40 age- and sex- matched normal
subjects participated in this study. Subjects were evaluated on performance of a tracking
task for motor function, and by the joint reposition test for integrity of proprioceptive
sense in the ipsilateral UL. [Result] The comparison of the stroke group and the control
group showed significant differences in performance of the tracking task and the joint
reposition test. The accuracy index for the tracking task showed significant correlation
with the error score for the joint reposition test in the stroke group. [Conclusion] These
results suggest that the ipsilateral UL of stroke patients has impairment in sensory
function which is related to proprioceptive sense, along with motor deficits. Therefore,
we think that the difficulty stroke patients experience with motor tasks for the
ipsilateral UL is induced by diminished integrity of sensorimotor function due to both
sensory and motor deficits.
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Nam SH, Son SM, Kwon JW, Lee NK. The Intra- and Inter-rater Reliabilities of the Forward Head Posture Assessment of Normal Healthy Subjects. J Phys Ther Sci 2013; 25:737-9. [PMID: 24259842 PMCID: PMC3804999 DOI: 10.1589/jpts.25.737] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Accepted: 02/15/2013] [Indexed: 12/25/2022] Open
Abstract
[Purpose] Assessment of posture is an important goal of physical therapy interventions for preventing the progression of forward head posture (FHP). The purpose of this study was to determine the inter- and intra-rater reliabilities of the assessment of FHP. [Subjects and Methods] We recruited 45 participants (20 male subjects, 25 female subjects) from a university student population. Two physical therapists assessed FHP using images of head extension. FHP is characterized by the measurement of angles and distances between anatomical landmarks. Forward shoulder angle of 54° or less was defined as FHP. Intra- and inter-rater reliabilities were estimated using Kendall's Taub correlation coefficients. [Results] Intra-class correlation of intra-rater measurements indicated an excellent level of reliability (0.91), and intra-class correlation of inter-rater measurements showed a good level of reliability in the assessment of FHP (0.75). [Conclusion] Assessment of FHP is an important component of evaluation and affects the design of the treatment regimen. The assessment of FHP was reliably measured by two physical therapists. It could therefore become a useful method for assessing FHP in the clinical setting. Future studies will be needed to provide more detailed quantitative data for accurate assessment of posture.
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Kwon JW, Nam SH, Lee NK, Son SM, Choi YW, Kim CS. The effect of transcranial direct current stimulation on the motor suppression in stop-signal task. NeuroRehabilitation 2013; 32:191-6. [DOI: 10.3233/nre-130836] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Choi J, Choi SY, Lee SY, Lee JY, Kim HS, Lee SY, Lee NK. Caffeine enhances osteoclast differentiation and maturation through p38 MAP kinase/Mitf and DC-STAMP/CtsK and TRAP pathway. Cell Signal 2013; 25:1222-7. [PMID: 23434822 DOI: 10.1016/j.cellsig.2013.02.015] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2012] [Revised: 01/25/2013] [Accepted: 02/13/2013] [Indexed: 11/26/2022]
Abstract
The consumption of caffeine from some common beverages has been associated with low bone mass by inducing urinary calcium loss and deceasing bone mineral density. However, the effect of caffeine on osteoclast differentiation is still unclear. Here, we demonstrate that caffeine directly enhances osteoclast differentiation and maturation. TRAP staining showed that the number of larger (>100 μm) osteoclastic cells as well as of TRAP-positive multinucleated cells was increased by caffeine treatment. Among the MAP kinases, caffeine specifically activated p38 MAP kinase, which in turn, controlled osteoclast differentiation and maturation. This is evidenced by the abolishment of activated p38 MAP kinase by pretreatment with SB203580, a p38-specific inhibitor, resulting in suppressed osteoclast differentiation and maturation that should be increased by caffeine. Caffeine significantly induced the expression of Mitf and pretreatment with SB203580 markedly suppressed the expression of Mitf induced by caffeine. Whereas it failed to regulate the expression of NFATc1 and Oscar, the expressions of Cathepsin K and TRAP were induced by caffeine treatment in primary preosteoclasts. Real-time PCR and luciferase assays showed that the increase of osteoclastic cell-cell fusion by caffeine was through the transcriptional up-regulation of DC-STAMP expression but not of Atp6v0d2. These results strongly suggest that caffeine directly enhances osteoclast differentiation and maturation through p38 MAP kinase activation, thus inducing Mitf expression and transcriptional activation of DC-STAMP, and finally CtsK and TRAP.
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Son SM, Kwon YH, Lee NK, Nam SH, Kim K. Deficits of Movement Accuracy and Proprioceptive Sense in the Ipsi-lesional Upper Limb of Patients with Hemiparetic Stroke. J Phys Ther Sci 2013. [DOI: 10.1589/jpts.25.5_567] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Son SM, Kwon JW, Nam SH, Lee NK, Kim K, Kim CS. Adverse effects of motor-related symptoms on the ipsilateral upper limb according to long-term cane usage. NeuroRehabilitation 2012; 31:137-41. [PMID: 22951707 DOI: 10.3233/nre-2012-0782] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
OBJECTIVE Although the cane is prescribed to aid in daily living and social participation in stroke patients, this study aimed to identify whether long-term cane usage affected sensorimotor functions in the distal part of the non-affected upper limb in relation to a tracking task, a nine-hole pegboard test, and proprioceptive joint sense. PATIENT AND METHOD Forty stroke patients who were divided into a cane using group (CUG) or a non-cane using group (NCUG) participated in this study. Subjects were evaluated in a tracking task for visuomotor coordination, a nine-hole pegboard test for dexterous hand motion, and a joint reposition test for proprioceptive sense integrity. RESULT Comparison of the CUG and NCUG revealed significant differences in performance of the tracking task, the nine-hole pegboard test, and the joint reposition test (p < 0.05). The CUG had more difficulty performing visuomotor coordination and dexterous hand motion tasks compared with the NCUG. Proprioceptive joint sense was also deteriorated in the CUG. CONCLUSION These results suggest that stroke patients who use a cane for a long period, could experience decreased sensorimotor function in the ipsilateral upper limb of a damaged hemisphere. Therefore, it will be necessary to provide careful evaluation and appropriate therapeutic intervention for stroke patients who require the use of a cane over a long period.
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Kim JH, Kang YJ, Kim DS, Lee CH, Jeon YS, Lee NK, Oh MH. The relationship between mast cell density and tumour grade in transitional cell carcinoma of the bladder. J Int Med Res 2012; 39:1675-81. [PMID: 22117967 DOI: 10.1177/147323001103900509] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
This study investigated the relationship between mast cell numbers and the grade of bladder transitional cell carcinoma (TCC). Bladder TCC biopsies were obtained via transurethral resection and 45 stage T1 specimens were included in the study. Specimens were sorted into two groups, low grade (grade I) and high grade (grades II and III). Samples were stained using haematoxylin and eosin, toluidine blue and immunohistochemical staining for tryptase. Mast cells were examined by light microscopy and cell density was recorded. Mast cell density was significantly higher in high-grade TCC than low-grade TCC. There was also a significant relationship between the number of mast cells identified using toluidine blue staining or immunohistochemical staining for tryptase. Detailed studies of mast cell function will enable the development of more effective antitumour therapies via mast cell manipulation.
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Yang YJ, Lee NK, Lee NY, Lee JW, Park SJ. Cell death mediated by Vibrio parahaemolyticus type III secretion system 1 is dependent on ERK1/2 MAPK, but independent of caspases. J Microbiol Biotechnol 2011; 21:903-13. [PMID: 21952366 DOI: 10.4014/jmb.1104.04044] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
Vibrio parahaemolyticus, which causes gastroenteritis, wound infection, and septicemia, has two sets of type III secretion systems (TTSS), TTSS1 and TTSS2. A TTSS1- deficient vcrD1 mutant of V. parahaemolyticus showed an attenuated cytotoxicity against HEp-2 cells, and a significant reduction in mouse lethality, which were both restored by complementation with the intact vcrD1 gene. V. parahaemolyticus also triggered phosphorylation of mitogenactivated protein kinases (MAPKs) including p38 and ERK1/2 in HEp-2 cells. The ability to activate p38 and ERK1/2 was significantly affected in a TTSS1-deficient vcrD1 mutant. Experiments using MAPK inhibitors showed that p38 and ERK1/2 MAPKs are involved in V. parahaemolyticus-induced death of HEp-2 cells. In addition, caspase-3 and caspase-9 were processed into active forms in V. parahaemolyticus-exposed HEp-2 cells, but activation of caspases was not essential for V. parahaemolyticusinduced death of HEp-2 cells, as shown by both annexin V staining and lactate dehydrogenase release assays. We conclude that secreted protein(s) of TTSS1 play an important role in activation of p38 and ERK1/2 in HEp-2 cells that eventually leads to cell death via a caspaseindependent mechanism.
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Lee NK, Kim S, Lee JW, Jeong YJ, Lee SH, Heo J, Kang DH. CT differentiation of pyogenic liver abscesses caused by Klebsiella pneumoniae vs non-Klebsiella pneumoniae. Br J Radiol 2010; 84:518-25. [PMID: 21081584 DOI: 10.1259/bjr/23004588] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
OBJECTIVE Klebsiella pneumoniae is one of the organisms most commonly isolated from pyogenic liver abscesses in Asian populations. We compared CT findings in liver abscesses caused by K. pneumoniae with those caused by other bacterial pathogens. METHODS Of 214 patients with liver abscesses examined over a 5 year period, 129 patients with positive blood or aspirate cultures were enrolled. The patients were divided into two groups: the K. pneumoniae monomicrobial liver abscess (KLA) group (n = 59) and the non-K. pneumoniae monomicrobial or polymicrobial liver abscess (non-KLA) group (n = 70). Two radiologists blinded to the culture results evaluated the CT images, recording the number, size, location and configuration of abscesses, the thickness of the abscess wall, the pattern of rim enhancement, septal enhancement, the double target sign, internal necrotic debris, internal gas bubbles and underlying biliary disease. The presence of diabetes and metastatic infection was also compared between groups. Statistical analyses were performed using univariate (Student's t-test and χ(2) test) and multivariate analyses. RESULTS Multivariate analysis showed that a thin wall, necrotic debris, metastatic infection and the absence of underlying biliary disease were the most significant predictors of KLA. When three of the four criteria were used in combination, a specificity of 98.6% was achieved for the diagnosis of KLA. CONCLUSION A thin-walled abscess, internal necrotic debris, the presence of metastatic infection and the absence of underlying biliary disease may be useful CT findings in the early diagnosis of K. pneumoniae liver abscesses.
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Chun JN, Choi B, Lee KW, Lee DJ, Kang DH, Lee JY, Song IS, Kim HI, Lee SH, Kim HS, Lee NK, Lee SY, Lee KJ, Kim J, Kang SW. Cytosolic Hsp60 is involved in the NF-kappaB-dependent survival of cancer cells via IKK regulation. PLoS One 2010; 5:e9422. [PMID: 20351780 PMCID: PMC2843631 DOI: 10.1371/journal.pone.0009422] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2009] [Accepted: 01/18/2010] [Indexed: 01/06/2023] Open
Abstract
Cytoplasmic presence of Hsp60, which is principally a nuclear gene-encoded mitochondrial chaperonin, has frequently been stated, but its role in intracellular signaling is largely unknown. In this study, we demonstrate that the cytosolic Hsp60 promotes the TNF-alpha-mediated activation of the IKK/NF-kappaB survival pathway via direct interaction with IKKalpha/beta in the cytoplasm. Selective loss or blockade of cytosolic Hsp60 by specific antisense oligonucleotide or neutralizing antibody diminished the IKK/NF-kappaB activation and the expression of NF-kappaB target genes, such as Bfl-1/A1 and MnSOD, which thus augmented intracellular ROS production and ASK1-dependent cell death, in response to TNF-alpha. Conversely, the ectopic expression of cytosol-targeted Hsp60 enhanced IKK/NF-kappaB activation. Mechanistically, the cytosolic Hsp60 enhanced IKK activation via upregulating the activation-dependent serine phosphorylation in a chaperone-independent manner. Furthermore, transgenic mouse study showed that the cytosolic Hsp60 suppressed hepatic cell death induced by diethylnitrosamine in vivo. The cytosolic Hsp60 is likely to be a regulatory component of IKK complex and it implicates the first mitochondrial factor that regulates cell survival via NF-kappaB pathway.
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Lee NK, Choi HK, Kim DK, Lee SY. Rac1 GTPase regulates osteoclast differentiation through TRANCE-induced NF-kappa B activation. Mol Cell Biochem 2009; 281:55-61. [PMID: 16328957 DOI: 10.1007/s11010-006-0333-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2005] [Accepted: 06/27/2005] [Indexed: 10/25/2022]
Abstract
Signaling by tumor necrosis factor (TNF)-related activation-induced cytokine (TRANCE) is essential for the differentiation of monocytes/macrophages into osteoclasts. We show here that TRANCE selectively activates Rac1, but not Rac2 in osteoclast precursors. Expression of a dominant interfering mutant of TNF receptor-associated factor (TRAF)6 blocks TRANCE-mediated Rac1 activation, indicating that Rac1 lies downstream of TRAF6. Osteoclast precursors expressing a dominant negative Rac1N17 are defective in TRANCE-induced IKK activation and IkappaBalpha degradation resulting in inhibition of NFkappaB-dependent reporter gene activity. In addition, Rac1 acts upstream of TAK1 to induce NF-kappaB activation and is required for the normal differentiation of osteoclast precursors. Thus, Rac1 may represent a key regulator for differentiation of osteoclasts through the activation of NF-kappaB.
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Lee NK, Karsenty G. Reciprocal regulation of bone and energy metabolism. JOURNAL OF MUSCULOSKELETAL & NEURONAL INTERACTIONS 2008; 8:351. [PMID: 19147972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
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Lee NK, Choi HK, Yoo HJ, Shin J, Lee SY. RANKL-induced schlafen2 is a positive regulator of osteoclastogenesis. Cell Signal 2008; 20:2302-8. [PMID: 18796328 DOI: 10.1016/j.cellsig.2008.08.019] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2008] [Revised: 08/27/2008] [Accepted: 08/27/2008] [Indexed: 11/16/2022]
Abstract
Osteoclasts are hematopoietic lineage derived-multinucleated cells that resorb bone. Their activity in balance with that of osteoblast is essential for bone homeostasis. Receptor activator of NF-kappaB ligand (RANKL) is known as an essential cytokine for the osteoclastogenesis, and c-Jun signaling in cooperation with NFAT family is crucial for RANKL-regulated osteoclastogenesis. We show here that schlafen2 (Slfn2), a member of a new family of growth regulatory genes involved in thymocyte development, is critical for osteoclastogenesis. RANKL selectively induces Slfn2 expression in osteoclast precursors via Rac1 signaling pathway. Targeted inhibition of Slfn2 by small interfering RNAs (siRNAs) markedly inhibits the formation of osteoclasts by diminishing the activation of c-Jun and the expression of c-Jun and NFATc1. In contrast, the overexpression of Slfn2 markedly increased phosphorylation and transactivation of c-Jun by RANKL. Together, these results indicate that Slfn2 has an essential role in osteoclastogenesis, functioning upstream of c-Jun and NFATc1.
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Lee NK, Karsenty G. Reciprocal regulation of bone and energy metabolism. Trends Endocrinol Metab 2008; 19:161-6. [PMID: 18407515 DOI: 10.1016/j.tem.2008.02.006] [Citation(s) in RCA: 135] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2008] [Revised: 02/12/2008] [Accepted: 02/25/2008] [Indexed: 12/24/2022]
Abstract
The finding that fat regulates bone metabolism was viewed as an indication that bone might regulate some aspects of energy metabolism in a feedback loop. The search that started nine years ago for a bone-derived hormone that regulates energy metabolism first took a convoluted path through the identification of a modifier gene. Once this hormone, osteocalcin, was identified, it became clear that bone exerts a profound and complex influence on glucose and fat metabolism. This review highlights the most important salient features of this novel regulation of energy metabolism.
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Cohen-Tannoudji L, Bertrand E, Baudry J, Robic C, Goubault C, Pellissier M, Johner A, Thalmann F, Lee NK, Marques CM, Bibette J. Measuring the kinetics of biomolecular recognition with magnetic colloids. PHYSICAL REVIEW LETTERS 2008; 100:108301. [PMID: 18352236 DOI: 10.1103/physrevlett.100.108301] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2007] [Indexed: 05/26/2023]
Abstract
We introduce a general methodology based on magnetic colloids to study the recognition kinetics of tethered biomolecules. Access to the full kinetics of the reaction is provided by an explicit measure of the time evolution of the reactant densities. Binding between a single ligand and its complementary receptor is here limited by the colloidal rotational diffusion. It occurs within a binding distance that can be extracted by a reaction-diffusion theory that properly accounts for the rotational Brownian dynamics. Our reaction geometry allows us to probe a large diversity of bioadhesive molecules and tethers, thus providing a quantitative guidance for designing more efficient reactive biomimetic surfaces, as required for diagnostic, therapeutic, and tissue engineering techniques.
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Lee NK, Sowa H, Hinoi E, Ferron M, Ahn JD, Confavreux C, Dacquin R, Mee PJ, McKee MD, Jung DY, Zhang Z, Kim JK, Mauvais-Jarvis F, Ducy P, Karsenty G. Endocrine regulation of energy metabolism by the skeleton. Cell 2007; 130:456-69. [PMID: 17693256 PMCID: PMC2013746 DOI: 10.1016/j.cell.2007.05.047] [Citation(s) in RCA: 1702] [Impact Index Per Article: 100.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2006] [Revised: 03/17/2007] [Accepted: 05/21/2007] [Indexed: 12/13/2022]
Abstract
The regulation of bone remodeling by an adipocyte-derived hormone implies that bone may exert a feedback control of energy homeostasis. To test this hypothesis we looked for genes expressed in osteoblasts, encoding signaling molecules and affecting energy metabolism. We show here that mice lacking the protein tyrosine phosphatase OST-PTP are hypoglycemic and are protected from obesity and glucose intolerance because of an increase in beta-cell proliferation, insulin secretion, and insulin sensitivity. In contrast, mice lacking the osteoblast-secreted molecule osteocalcin display decreased beta-cell proliferation, glucose intolerance, and insulin resistance. Removing one Osteocalcin allele from OST-PTP-deficient mice corrects their metabolic phenotype. Ex vivo, osteocalcin can stimulate CyclinD1 and Insulin expression in beta-cells and Adiponectin, an insulin-sensitizing adipokine, in adipocytes; in vivo osteocalcin can improve glucose tolerance. By revealing that the skeleton exerts an endocrine regulation of sugar homeostasis this study expands the biological importance of this organ and our understanding of energy metabolism.
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Lee NK, Lee SY. Modulation of life and death by the tumor necrosis factor receptor-associated factors (TRAFs). BMB Rep 2005; 35:61-6. [PMID: 16248971 DOI: 10.5483/bmbrep.2002.35.1.061] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
The TNF receptor-associated factor (TRAF) family is a group of adapter proteins that link a wide variety of cell surface receptors. Including the TNF and IL-1 receptor superfamily to diverse signaling cascades, which lead to the activation of NF-kappaB and mitogen-activated protein kinases. In addition, TRAFs interact with a variety of proteins that regulate receptor-induced cell death or survival. Thus, TRAF-mediated signals may directly induce cell survival or interfere with the death receptor-induced apoptosis.
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Han SY, Lee NK, Kim KH, Jang IW, Yim M, Kim JH, Lee WJ, Lee SY. Transcriptional induction of cyclooxygenase-2 in osteoclast precursors is involved in RANKL-induced osteoclastogenesis. Blood 2005; 106:1240-5. [PMID: 15860667 DOI: 10.1182/blood-2004-12-4975] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
AbstractRegulation of osteoclast differentiation is key to understanding the pathogenesis and to developing treatments for bone diseases such as osteoporosis. To gain insight into the mechanism of the receptor activator of nuclear factor (NF)–κB ligand (RANKL)–specific induction of the osteoclast differentiation program, we took a suppression-subtractive hybridization screening approach to identify genes specifically induced via the RANKL-Rac1 signaling pathway. Among identified targets, we show that RANKL selectively induces cyclooxygenase (COX) 2 expression via Rac1 that results in turn in production of prostaglandin E2 (PGE2) in RAW 264.7 cells. By using transient transfection assays, we found that the –233/–206 region of the COX-2 promoter gene was critical for RANKL-induced promoter activity. This RANKL-responsive region contained an NF-κB site that, when mutated, completely abolished the induction of NF-κB DNA-binding activity by RANKL. Blockade of COX-2 by celecoxib inhibits differentiation of bone marrow-derived monocyte/macrophage precursor cells (BMMs) into tartrate-resistant acid phosphatase-positive (TRAP+) osteoclastic cells. This inhibition can be rescued by the addition of exogenous PGE2, suggesting that COX-2–dependent PGE2 induction by RANKL in osteoclast precursors is required for osteoclast differentiation.
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