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Dreborg S, Lee TH, Kay AB, Durham SR. Immunotherapy is allergen-specific: a double-blind trial of mite or timothy extract in mite and grass dual-allergic patients. Int Arch Allergy Immunol 2011; 158:63-70. [PMID: 22212720 DOI: 10.1159/000330649] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2011] [Accepted: 06/22/2011] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND One hundred years ago, Noon [Lancet 1911;1:1572-1573], using conjunctival provocation testing (CPT), was the first to demonstrate the effectiveness of subcutaneous immunotherapy (SCIT) in grass-allergic subjects with hay fever. In this centenary year, we present data that, by use of CPT and allergen-specific IgG, replicate this observation and additionally confirm the allergen specificity of SCIT by using a double-blind design employing either grass or mite SCIT in dual grass- and mite-allergic individuals. METHODS Twenty adults (11 females) with perennial rhinoconjunctivitis and exacerbation of symptoms during the grass pollen season and in the autumn had immediate skin and conjunctival sensitivity and raised specific IgE to both Dermatophagoides farinae and Phleum pratense. Participants were randomly assigned to either timothy or D. farinae immunotherapy for 3 years. CPT and specific IgG tests to both allergens were performed annually. After 3 years, subjects gave their blinded overall evaluation. RESULTS Six mild-to-moderate general reactions occurred in 2 timothy- and 4 mite-treated patients. Four of these patients and 2 other patients withdrew from the study. Seven patients in each group completed the study. After 3 years of immunotherapy, the timothy CPT threshold concentration had increased 16- fold in timothy-treated patients (p < 0.05; between-group change, p < 0.05). The increase in the mite CPT threshold in mite- compared to grass-treated patients was 31-fold (p < 0.05). The overall assessment of conjunctival sensitivity was highly significant in favour of treatment (p < 0.015), as was that of allergen-specific IgG (p < 0.0001). CONCLUSIONS Allergen immunotherapy is allergen species-specific, as judged by decreased conjunctival sensitivity and changes in allergen-specific IgG concentrations.
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Kim DS, Kim DH, Goo B, Cho YH, Park JM, Lee TH, Kim HO, Kim HS, Lee H, Lee JD, Byamba D, Je JH, Lee MG. Immunotherapy of malignant melanoma with tumor lysate-pulsed autologous monocyte-derived dendritic cells. Yonsei Med J 2011; 52:990-8. [PMID: 22028165 PMCID: PMC3220245 DOI: 10.3349/ymj.2011.52.6.990] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
PURPOSE Dendritic cell (DC) vaccination for melanoma was introduced because melanoma carries distinct tumor-associated antigens. The purpose of this study was to investigate the efficacy and safety of DC vaccination for melanoma in Korea. MATERIALS AND METHODS Five patients with stage IV and one with stage II were enrolled. Autologous monocyte-derived DCs (MoDCs) were cultured and pulsed with tumor-lysate, keyhole limpet hemocyanin, and cytokine cocktail for mature antigen-loaded DC. DC vaccination was repeated four times at 2-week intervals and 2-4×10⁷ DC were injected each time. RESULTS Reduced tumor volume was observed by PET-CT in three patients after DC vaccination. Delayed type hypersensitivity responses against tumor antigen were induced in five patients. Tumor antigen-specific IFN-γ-producing peripheral blood mononuclear cells were detected with enzyme-linked immunosorbent spot in two patients. However, the overall clinical outcome showed disease progression in all patients. CONCLUSION In this study, DC vaccination using tumor antigen-loaded, mature MoDCs led to tumor regression in individual melanoma patients. Further standardization of DC vaccination protocol is required to determine which parameters lead to better anti-tumor responses and clinical outcomes.
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Park JH, Kang HS, Han MH, Jeon P, Yoo DS, Lee TH. Embolization of intracranial aneurysms with HydroSoft coils: results of the Korean multicenter study. AJNR Am J Neuroradiol 2011; 32:1756-61. [PMID: 21920861 DOI: 10.3174/ajnr.a2633] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Various modifications of detachable coils have been attempted to reduce recurrence rates in aneurysmal coil embolization and HydroSoft coil is one of them. The authors report their experience using HydroSoft coils in the treatment of cerebral aneurysms. MATERIALS AND METHODS The present study is a prospective multicenter observational series of 127 aneurysms in 120 patients treated with HydroSoft coils. RESULTS Ten centers participated in this study, and there were 92 (72%) unruptured and 35 ruptured aneurysms. Aneurysm volumes were ≥ 100 mm³ in 21 (17%) and < 100 mm³ in 106 (83%) (mean, 56 mm³; range, 5-249 mm³). The average percentage length of HydroSoft coils detached in treated aneurysms was 67% (range, 42%-100%). Immediate postprocedural angiography demonstrated complete aneurysm occlusion in 69% (87/127 aneurysms), residual neck in 20% (25/127), and residual sac in 12% (15/127). Procedure-related adverse events occurred in 4.7% (6/127 aneurysms), including procedural bleeding (5/127) and thromboembolism (2/127), and immediate procedure-related morbidity and mortality rates were 0.8% and 0%. Conventional angiography or MRA follow-up was performed in 83% (105/127) at ≥ 6 months after treatment (mean interval, 11 months; range, 6-24 months). The overall recanalization rate was 3% (3/105 aneurysms; 2 major and 1 minor recanalizations). Progression to complete aneurysmal occlusion was noted in 20 of 27 aneurysms (74%) during the follow-up. CONCLUSIONS The safety profile of HydroSoft coils appears acceptable. In terms of initial occlusion rates and durability, embolization by using HydroSoft coils seems to be favorable compared with most large series of pure platinum or coated coils.
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Lee TH, Elliott SR. Ab Initio computer simulation of the early stages of crystallization: application to Ge(2)Sb(2)Te(5) phase-change materials. PHYSICAL REVIEW LETTERS 2011; 107:145702. [PMID: 22107213 DOI: 10.1103/physrevlett.107.145702] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2011] [Revised: 07/30/2011] [Indexed: 05/31/2023]
Abstract
By virtue of the ultrashort phase-transition time of phase-change memory materials, e.g., Ge(2)Sb(2)Te(5), we successfully reproduce the early stages of crystallization in such a material using ab initio molecular-dynamics simulations. A stochastic distribution in the crystallization onset time is found, as generally assumed in classical nucleation theory. The critical crystal nucleus is estimated to comprise 5-10 (Ge,Sb)(4)Te(4) cubes. Simulated growth rates of crystalline clusters in amorphous Ge(2)Sb(2)Te(5) are consistent with extrapolated experimental measurements. The formation of ordered planar structures in the amorphous phase plays a critical role in lowering the interfacial energy between crystalline clusters and the amorphous phase, which explains why Ge-Sb-Te materials exhibit ultrafast crystallization.
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Fang C, Meng Q, Wu H, Eid G, Zhang G, Zhang X, Yang S, Huang K, Lee TH, Corrigan CJ, Ying S. Resistin-like molecule-β is a human airway remodelling mediator. Eur Respir J 2011; 39:458-66. [PMID: 21828035 DOI: 10.1183/09031936.00107811] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Though implicated in vascular remodelling, a role for the resistin-like molecule (RELM)-β in human airway remodelling remains unexplored. We hypothesised that RELM-β expression is increased in the airways of asthmatics and regulates airways epithelial cell function. Expression of RELM-β in the bronchial mucosa and its concentrations in bronchoalveolar lavage (BAL) fluid from asthmatics and controls were measured by immunohistochemistry and ELISA, respectively. Proliferation assays, Western blotting, ELISA and real-time PCR were employed to detect effects of RELM-β on airways epithelial cells. RELM-β expression was increased in the bronchial mucosa and BAL fluid of asthmatics compared with controls. In the asthmatics, the numbers of mucosal RELM-β+ cells correlated inversely with forced expiratory volume in 1 s (r=-0.531, p=0.016), while the numbers of epithelial RELM-β+ cells correlated positively with those of mucin (MUC)5AC+ cells. In vitro, interleukin-13 enhanced RELM-β expression by primary human airways epithelial cells, while RELM-β itself acted on these cells to induce proliferation, expression of MUC5AC, extracellular signal-regulated kinase (ERK)/mitogen-activated protein kinase (MAPK)-phosphatidylinositol 3-kinase (PI3K)/Akt phosphorylation and elevated expression of transforming growth factor-β2, epidermal growth factor and vascular endothelial growth factor. RELM-β has the potential to contribute to airway remodelling in diseases such as asthma by acting on epithelial cells to increase proliferation, mucin and growth factor production, at least partly via ERK/MAPK-PI3K/Akt signalling pathways.
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Lee TH, Park DH, Lee SS, Seo DW, Park SH, Lee SK, Kim MH, Kim SJ. Outcomes of endoscopic transpapillary gallbladder stenting for symptomatic gallbladder diseases: a multicenter prospective follow-up study. Endoscopy 2011; 43:702-8. [PMID: 21425042 DOI: 10.1055/s-0030-1256226] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND AND STUDY AIMS Endoscopic transpapillary gallbladder drainage for symptomatic gallbladder disease is a safe and effective bridge therapy in patients at high risk for surgery or who have terminal liver disease and are awaiting transplantation. However, there are few reports on long-term results in terms of stent patency and clinical course. Our study was designed to investigate the long-term patency and clinical course after endoscopic transpapillary gallbladder stenting (ETGS) in patients with symptomatic gallbladder disease. PATIENTS AND METHODS A total of 29 patients who were unsuitable for cholecystectomy underwent ETGS from June 2006 to March 2010 using a 7-Fr double-pigtail stent between the gallbladder and the duodenum. Their clinical progress, adverse events, and stent patency after ETGS were recorded prospectively in two tertiary referral centers. RESULTS Technically, ETGS was successful in 23 (79.3%) of the 29 patients. The mean procedure time was 22.4 ± 11.5 min. Postprocedure adverse events were mild pancreatitis (8.7%) and cholestasis (8.7%), all of which resolved with conservative management. During the follow-up period (median 586 days, range 11-1403 days), 20 patients were analyzed as per protocol, and scheduled follow-up was performed. Late adverse events developed in four patients (20%), including distal migration (n = 2), cholangitis (n = 1), and recurrent biliary pain (n = 1). The remaining 16 patients were followed for more than 12 months (nine patients were followed for more than 24 months). Median stent patency was 760 days, as determined by the Kaplan-Meier method. CONCLUSIONS As a primary therapy, ETGS is technically feasible and effective in patients who are unsuitable for cholecystectomy. ETGS may also provide long-term stent patency without the need for scheduled stent exchanges.
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Tam CL, Foo YC, Lee TH. The association between perceived social support, socio-economic status and mental health in young Malaysian adults. East Asian Arch Psychiatry 2011; 21:73-78. [PMID: 21838210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
OBJECTIVES To examine gender differences in mental health and perceived social support, relationship between parents' income and mental health, and differences in mental health across education levels. METHODS A total of 303 students aged 16 to 26 years were recruited from Selangor, Malaysia. The Multidimensional Scale of Perceived Social Support and General Health Questionnaire were used to measure the level of perceived social support and the mental health status. Demographic data, including education level and parents' income, were also obtained. RESULTS Females perceived significantly higher levels of overall social support than males (t = -2.7; p < 0.05). However, there were no significant differences in mental health status between males and females (t = -1.8; p > 0.05), as well as mental health status among different parental income groups (chi2 = 5.0; p > 0.05) and the education levels of the subjects (chi2 = 0.7; p > 0.05). A more favourable mental health status of the subjects was associated with higher parental incomes (r = -0.1; p < 0.05). CONCLUSIONS There were gender differences for perceived social support, but not for mental health status in older adolescents and young adults. There was also a relationship between parental income and an individual's mental health status, but mental health was not related to their education level.
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Kim IS, Song YM, Cho TH, Pan H, Lee TH, Kim SJ, Hwang SJ. Biphasic Electrical Targeting Plays a Significant Role in Schwann Cell Activation. Tissue Eng Part A 2011; 17:1327-40. [DOI: 10.1089/ten.tea.2010.0519] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
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Lee TH, Pan H, Kim IS, Hwang SJ, Kim SJ. Functional regeneration of severed peripheral nerve using an implantable electrical stimulator. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2011; 2010:1511-4. [PMID: 21096369 DOI: 10.1109/iembs.2010.5626837] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
This paper presents functional regeneration of severed peripheral nerve using a polymer-based implantable electrical stimulator. A polyimide based conduit electrode was made by micro-fabrication and a stimulation chip was designed to generate biphasic current pulse for electrical stimulation. The stimulation chip was packaged with a battery using silicone elastomer, and integrated with the electrode. The implantable electrical stimulator was implanted in the rat sciatic nerve with 7 mm gap. The electrical stimulation was applied for periods of one, two and four weeks between the proximal and the distal nerve stumps. After four weeks of post-operations, the degree of regeneration was evaluated through walking track assessments and by measuring neural response of the regenerated nerve. Based on these results, electrical stimulation, especially for two weeks of stimulation, could accelerate functional regeneration of the severed nerve.
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Kim JH, Lee TH, Song YM, Kim IS, Cho TH, Hwang SJ, Kim SJ. An implantable electrical bioreactor for enhancement of cell viability. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2011; 2011:3601-3604. [PMID: 22255118 DOI: 10.1109/iembs.2011.6090603] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Low survival of injected cells which are prepared by ex-vivo culture is main obstacle in cell-based tissue regeneration. To elevate cell adaptation, we designed an implantable electrical bioreactor where human mesenchymal stromal cells (hMSCs) can be cultured and stimulated electrically. Bioreactor was composed of biocompatible cylindrical Teflon body containing a flexible polyimide electrode and implantable stimulator. The Teflon body has about 300 holes with a diameter of 300 um for effective nutrients supply inside the bioreactor and has a length of 17 mm and a diameter of 8mm for implantation. After hMSCs seeded on the collagen sponge that serves as scaffold to form a bone tissue graft, they are cultured in the bioreactor with biphasic electric current (BEC) stimulation. BEC stimulation with amplitude of 20/40 uA, duration of 100 us and a frequency of 100 Hz was applied for one week in the early stage of cultivation. Subsequently, after hMSCS were cultured for another week without electrical stimulation, cell response such as cell proliferation, cell attachment and gene expression are evaluated. In vitro and In vivo culture of hMSCs showed 19% and 22% increase in cell proliferation at stimulated groups, compared to unstimulated control. The expression of type I collagen increased significantly at stimulated group. These results suggest that the usage of implantable electrical bioreactor can be a good strategy to enhance the efficiency of stem cell-based tissue engineering.
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Yang JK, Kim YS, Kim KI, Koo HS, Kim SM, Lee TH, Im EH, Huh KC, Choi YW, Kang YW, Kwon SJ. A case of esophageal and endobronchial anthracosis. Endoscopy 2010; 42 Suppl 2:E150-1. [PMID: 20486083 DOI: 10.1055/s-0029-1215417] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
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Alrashdan MS, Park JC, Sung MA, Yoo SB, Jahng JW, Lee TH, Kim SJ, Lee JH. Thirty minutes of low intensity electrical stimulation promotes nerve regeneration after sciatic nerve crush injury in a rat model. Acta Neurol Belg 2010; 110:168-179. [PMID: 20873447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We investigated whether electrical stimulation (ES) applied directly for 30 minutes after crushing injury to the sciatic nerves of rats could improve nerve regeneration. Two groups of animals were used in this study (n = 20 each): the ES group received 30 minutes of low intensity ES (20 Hz pulse rate, 2 uA amplitude) immediately after a standard crush injury, while the control group received no stimulation after injury. Both groups were followed up for three weeks. The sciatic function index (SFI) was calculated weekly. Mean conduction velocity (MCV) and peak voltage (PV) were calculated, and the sensory neurons in L4 and L5 dorsal root ganglia (DRG) were traced with Fluorogold in retrograde fashion and quantified at the end of the follow up period. Histomorphometric studies were also carried out in both groups. The ES group showed improved functional and sensory recovery compared to the control group three weeks after injury. SFI, MCV and the number of retrogradely labeled sensory neurons were significantly higher in the ES group. Additionally, axon counts, myelin thicknesses and G-ratio values were also higher in the ES group. Quantitative real-time reverse transcriptase-polymerase chain reaction (RT-PCR) showed an elevated expression of brain derived neurotrophic factor (BDNF) in DRG sensory neurons of the ES group five days post-injury. Here, we present the first evidence that the application of ES for 30 minutes immediately following crush injury is effective to promote nerve regeneration in a rat sciatic nerve model.
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Kim HJ, Jeong WC, Kim YT, Minhas AS, Lee TH, Lim CY, Park HM, Seo JK, Woo EJ. In vivoconductivity imaging of canine male pelvis using a 3T MREIT system. ACTA ACUST UNITED AC 2010. [DOI: 10.1088/1742-6596/224/1/012020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Jeong WC, Kim YT, Minhas AS, Lee TH, Kim HJ, Nam HS, Kwon O, Woo EJ. In vivoconductivity imaging of human knee using 3 mA injection current in MREIT. ACTA ACUST UNITED AC 2010. [DOI: 10.1088/1742-6596/224/1/012148] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Moon SE, Lee HY, Park J, Lee JW, Choi NJ, Park SJ, Kwak JH, Park KH, Kim J, Cho GH, Lee TH, Maeng S, Udrea F, Milne WI. Low power consumption and high sensitivity carbon monoxide gas sensor using indium oxide nanowire. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2010; 10:3189-3192. [PMID: 20358919 DOI: 10.1166/jnn.2010.2262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
In this paper, micro gas sensor was fabricated using indium oxide nanowire for effective gas detection and monitoring system. Indium oxide nanowire was grown using thermal CVD, and their structural properties were examined by the SEM, XRD and TEM. The electric properties for microdropped indium oxide nanowire device were measured, and gas response characteristics were examined for CO gas. Sensors showed high sensitivity and stability for CO gas. And with below 20 mw power consumption, 5 ppm CO could be detected.
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Kibria MG, Zhang F, Lee TH, Kim MJ, Howlader MMR. Comprehensive investigation of sequential plasma activated Si/Si bonded interfaces for nano-integration on the wafer scale. NANOTECHNOLOGY 2010; 21:134011. [PMID: 20208123 DOI: 10.1088/0957-4484/21/13/134011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The sequentially plasma activated bonding of silicon wafers has been investigated to facilitate the development of chemical free, room temperature and spontaneous bonding required for nanostructure integration on the wafer scale. The contact angle of the surface and the electrical and nanostructural behavior of the interface have been studied. The contact angle measurements show that the sequentially plasma (reactive ion etching plasma followed by microwave radicals) treated surfaces offer highly reactive and hydrophilic surfaces. These highly reactive surfaces allow spontaneous integration at the nanometer scale without any chemicals, external pressure or heating. Electrical characteristics show that the current transportation across the nanobonded interface is dependent on the plasma parameters. High resolution transmission electron microscopy results confirm nanometer scale bonding which is needed for the integration of nanostructures. The findings can be applied in spontaneous integration of nanostructures such as nanowires/nanotubes/quantum dots on the wafer scale.
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Lee TH, Park SH, Lee CK, Chung IK, Kim SJ, Kang CH. Life-threatening hemorrhage following large-balloon endoscopic papillary dilation successfully treated with angiographic embolization. Endoscopy 2009; 41 Suppl 2:E241-2. [PMID: 19757375 DOI: 10.1055/s-0029-1214984] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Kang JSL, Cherian A, Gan SH, Lee TH, Lee KC, Chee CBE, Doherty TM, Wang YT, Seah GT. Strong purified protein derivative responses are associated with poor mycobacterium inhibition in latent TB. Eur Respir J 2009; 36:348-54. [PMID: 19996195 DOI: 10.1183/09031936.00063209] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The tuberculin skin test (TST) using purified protein derivative (PPD) of Mycobacterium tuberculosis is traditionally used to diagnose latent tuberculosis (TB) infection (LTBI). However, LTBI diagnosis by peripheral blood mononuclear cell (PBMC) interferon (IFN)-gamma responses to M. tuberculosis-specific antigens, early secreted antigenic target 6 kDa (ESAT-6) and culture filtrate protein (CFP)-10 has greater specificity. We investigated the difference in antimycobacterium cellular immunity in TB contacts who were strong TST reactors but nonresponsive to the ESAT-6/CFP-10 assay compared with those with concordant results. Healthy TB contacts were tested using the above two assays and mycobacterium survival was measured after co-culture of infected macrophages with their PBMCs. Whether PPD reactivity was tested by TST or by PBMC-specific IFN-gamma responses, strongly PPD-reactive TB contacts without ESAT-6/CFP-10 responsiveness showed significantly better mycobacterium inhibition activity than ESAT-6/CFP-10-responsive TB contacts with the same PPD reactivity. In the former group, stronger PPD reactivity was associated with improved mycobacterium killing, whereas ESAT-6/CFP-10 responders showed the opposite result. PPD-reactive ESAT-6/CFP-10-nonresponsive TB contacts in our population may have had protective immunity related to prior mycobacterium exposure. ESAT-6/CFP10-responsive TB contacts are more likely to have LTBI and, in this group, strong PPD reactivity may paradoxically be associated with poor mycobactericidal activity.
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Kim IS, Song JK, Song YM, Cho TH, Lee TH, Lim SS, Kim SJ, Hwang SJ. Novel effect of biphasic electric current on in vitro osteogenesis and cytokine production in human mesenchymal stromal cells. Tissue Eng Part A 2009; 15:2411-22. [PMID: 19292669 DOI: 10.1089/ten.tea.2008.0554] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Electrical stimulation (ES) can activate diverse biostimulatory responses in a range of tissues. Of various forms of ES, the application of biphasic electric current (BEC) is a new approach to bone formation. This study is to investigate the effects and mechanism of action of BEC in osteoblast differentiation and cytokine production in human mesenchymal stromal cells (hMSCs). Using an in vitro culture system with a modified version of the BEC stimulator chip used in our previous study, we exposed hMSCs to a 100 Hz ES with a magnitude of 1.5/15 muA/cm(2) for 250/25 mus. hMSCs showed increased proliferation during static BEC stimulation for 5 days. However, alkaline phosphatase activity and calcium deposition were enhanced in hMSCs 7 days after the stimulation, rather than during the period of ES. BEC induced vascular endothelial growth factor (VEGF) and BMP-2 production; the former can enhance the proliferation of human umbilical vein endothelial cells in culture using conditioned media from BEC cultures. Treatment with selective inhibitors of p38 MAPK (SB203580) or Erk (PD98059), as well as calcium channel blockers (verapamil and nifedipine), reduced the BEC-mediated increase of VEGF expression and cell proliferation. These findings reveal that BEC is involved in the osteoblast differentiation of hMSCs through enhancement of cell proliferation and modulation of the local endocrine environment through VEGF and BMP-2 induction through the activation of MAPK (Erk and p38) and the calcium channel. Thus, local stimulation using BEC might be most beneficial in promoting osteogenic differentiation of hMSCs, resulting in enhanced bone formation for bone tissue engineering.
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Lee CK, Park JY, Lee TH, Lee SH, Chung IK, Park SH, Kim HS, Kim SJ. Superselective microcoil embolization for endoscopically uncontrollable bleeding after endoscopic submucosal dissection. Endoscopy 2009; 41 Suppl 2:E109-10. [PMID: 19544251 DOI: 10.1055/s-0029-1214627] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Su L, Lee TH, Elliott SR. Evanescent-wave excitation of surface-enhanced Raman scattering substrates by an optical-fiber taper. OPTICS LETTERS 2009; 34:2685-2687. [PMID: 19724532 DOI: 10.1364/ol.34.002685] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We present a way of guiding light to planar surface-enhanced Raman scattering (SERS) substrates by using evanescent-wave coupling. Using nanostructured chalcogenide glass-based SERS substrates, we experimentally show the incident-angle dependence of plasmon resonances of the SERS substrates, demonstrating strong resonances at large incident angles. This allows the evanescent-wave excitation of SERS substrates through tapered optical fibers. Experiments show that fiber-taper-excited SERS substrates exhibit a significant enhancement of the Raman spectra of Rhodamine-6G analyte molecules. This configuration forms the basis of fiber-optic-based, reproducible, highly compact, and sensitive SERS systems.
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Corrigan CJ, Jayaratnam A, Wang Y, Liu Y, de Waal Malefyt R, Meng Q, Kay AB, Phipps S, Lee TH, Ying S. Early production of thymic stromal lymphopoietin precedes infiltration of dendritic cells expressing its receptor in allergen-induced late phase cutaneous responses in atopic subjects. Allergy 2009; 64:1014-22. [PMID: 19187393 DOI: 10.1111/j.1398-9995.2009.01947.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
BACKGROUND Thymic stromal lymphopoietin (TSLP) is an interleukin (IL)-7-like cytokine that triggers dendritic cell-mediated T helper (Th)2 inflammatory responses through a receptor consisting of a heterodimer of the IL-7 receptor alpha (IL-7Ralpha) chain and the TSLP receptor (TSLPR), which resembles the cytokine receptor common gamma chain. Dendritic cells activated by TSLP prime development of CD4(+) T cells into Th2 cells contributing to the pathogenesis of allergic inflammation. We hypothesized that allergen exposure induces expression of TSLP and results in recruitment of TSLPR bearing cells in the cutaneous allergen-induced late-phase reaction (LPR) in atopic subjects. METHODS Skin biopsies were obtained from atopic subjects (n = 9) at various times after cutaneous allergen challenge. In situ hybridization and immunohistochemistry were used to determine TSLP mRNA expression and to measure infiltration of TSLPR(+) DC in skin LPR. RT-PCR and flow cytometry were employed to analyse TSLPR expression on isolated blood DC. RESULTS Allergen-induced skin TSLP expression occurred as early as 1 h after allergen challenge, whereas TSLPR(+) and CD11c(+) cells infiltrated relatively late (24-48 h). The majority of TSLPR(+) cells were DC co-expressing blood DC antigen-1 (BDCA-1) or BDCA-2. Freshly isolated blood DC expressed both TSLPR and IL-7Ralpha chains. Maturation and stimulation with TSLP or polyriboinosinic-polyribocytidylic acid in vitro upregulated the expression of both TSLPR and IL-7Ralpha chains in DC but not in chemoattractant receptor-homologous molecule expressed on Th2 cells(+) CD4(+) T cells. CONCLUSION The data suggest that TSLP plays a role in augmenting, through DC recruitment and activation, the development of Th2-type T cells in allergic inflammation.
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MESH Headings
- Adolescent
- Adult
- Allergens/immunology
- Antigens, CD1
- Antigens, Surface/immunology
- Antigens, Surface/metabolism
- CD4-Positive T-Lymphocytes/drug effects
- CD4-Positive T-Lymphocytes/immunology
- CD4-Positive T-Lymphocytes/metabolism
- Cytokines/biosynthesis
- Cytokines/immunology
- Cytokines/pharmacology
- Dendritic Cells/drug effects
- Dendritic Cells/immunology
- Dendritic Cells/metabolism
- Glycoproteins
- Humans
- Hypersensitivity/immunology
- Hypersensitivity/metabolism
- Interferon Inducers/pharmacology
- Interleukin-15/pharmacology
- Interleukin-7/pharmacology
- Lectins, C-Type/immunology
- Lectins, C-Type/metabolism
- Membrane Glycoproteins/immunology
- Membrane Glycoproteins/metabolism
- Middle Aged
- Poly I-C/pharmacology
- Receptors, Cytokine/agonists
- Receptors, Cytokine/immunology
- Receptors, Cytokine/metabolism
- Receptors, Immunologic/immunology
- Receptors, Immunologic/metabolism
- Receptors, Interleukin-7/agonists
- Receptors, Interleukin-7/immunology
- Receptors, Interleukin-7/metabolism
- Skin/immunology
- Skin/pathology
- Young Adult
- Thymic Stromal Lymphopoietin
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Lee CK, Lee SH, Park JY, Lee TH, Chung IK, Park SH, Kim HS, Kim SJ. Appendiceal intussusception due to a fecalith mimicking a submucosal tumor. Endoscopy 2009; 41 Suppl 2:E25-6. [PMID: 19219765 DOI: 10.1055/s-0028-1103471] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
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Tan KK, Tang KZ, Huang S, Putra AS, Lee TH, Ng SC, Chan JKY, Tan LG, Chong MSK. Ex utero harvest of hematopoietic stem cells from placenta/umbilical cord with an automated collection system. IEEE Trans Biomed Eng 2009; 56:2331-4. [PMID: 19497809 DOI: 10.1109/tbme.2009.2023993] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Hematopoietic stem cells (HSCs) from the human placenta and umbilical cord blood (UCB) provide a rich source of highly proliferative cells for many clinical uses with advantages over traditional sources like the bone marrow and periphery blood. However, the key current constraint with this source of HSCs is the inadequate number of HSCs cells that can be harvested in a single collection using current approaches, which render a large number of collections unusable on their own, even for pediatric patients. This paper will present the development of a device to enable more efficient harvesting of HSCs from placentas, which can be used ex utero, upon the discharge of placentas after deliveries. The device can be used to facilitate a two-fraction collection process. Results, in terms of mononucleated cells (MNCs) count, CD34+ cells count, as well as flow cytometry, will be furnished to verify the effectiveness of the developed system.
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