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Park JK, Nam SH, Kwon HC, Mohamed AAH, Lee JK, Kim GC. Feasibility of nonthermal atmospheric pressure plasma for intracoronal bleaching. Int Endod J 2010; 44:170-5. [PMID: 21091514 DOI: 10.1111/j.1365-2591.2010.01828.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIM To investigate the effect of nonthermal atmospheric pressure plasma on intracoronal tooth bleaching in blood stained human teeth. METHODOLOGY Forty extracted single-root and blood stained human teeth were used. The teeth were randomly divided into two groups (n=20): group 1 received 30% HP activated by nonthermal atmospheric pressure plasma in the pulp chamber for 30 min, whilst group 2 received 30% HP alone in the pulp chamber for 30 min. The overall colour changes (ΔE) were assessed using the Commission Internationale de L'Eclairage (CIE) Lab Colour System. The data were analysed using Student's t-test to determine the significant differences. RESULTS The temperature of all teeth was maintained at approximately 37 °C during plasma bleaching. The plasma treatment with 30% HP resulted in significantly higher bleaching efficacy compared to 30% HP alone in discoloured teeth (P<0.05). The average ΔE values of group 1 and group 2 were 9.24 (0.37) and 4.47 (1.62), respectively, at 30 min. CONCLUSIONS The application of nonthermal atmospheric pressure plasma to intracoronal bleaching could be a novel and efficient therapy in the bleaching of haemorrhagically stained teeth.
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Suh DI, Lee JK, Kim CK, Koh YY. Bronchial hyperresponsiveness to methacholine/AMP and the bronchodilator response in asthmatic children. Eur Respir J 2010; 37:800-5. [PMID: 20817709 DOI: 10.1183/09031936.00049610] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Bronchodilator response (BDR) is assessed to estimate the reversibility of airflow obstruction. Bronchial hyperresponsiveness (BHR) is a characteristic feature of asthma and is usually measured by means of bronchial challenges using direct or indirect stimuli. The aim of the present study was to compare BHR to methacholine (direct) and that to adenosine 5'-monophosphate (AMP) (indirect) with regard to their relationships to BDR in asthmatic children. Methacholine and AMP challenge tests were performed on 138 children with mild-to-moderate asthma, and the provocative concentration causing a 20% decline in forced expiratory volume in 1 s (FEV₁) (PC₂₀) was determined for each challenge. BDR was calculated as the change in FEV(1), expressed as a percentage of the initial value, after inhalation of 400 μg salbutamol. Methacholine PC₂₀ correlated significantly but weakly with BDR (r = -0.254; p = 0.003). However, there was a significant and strong correlation between AMP PC₂₀ and BDR (r = -0.489; p = 0.000). For AMP PC₂₀, the relationship was closer than for methacholine PC₂₀ (p = 0.024 for comparison between correlation coefficients). The same figures were observed when BDR was expressed as a percentage of the predicted value. A stronger correlation of BDR with AMP PC₂₀ than with methacholine PC₂₀ suggests that BDR may be better reflected by BHR as assessed by AMP challenge than by methacholine challenge.
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Yoo KY, Jeong CW, Kim WM, Lee HK, Kim SJ, Jeong ST, Lee JK, Lee J. Fatal cerebral hemorrhage associated with autonomic hyperreflexia during surgery in the prone position in a quadriplegic patient: a case report. Minerva Anestesiol 2010; 76:554-558. [PMID: 20613698] [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
Intracerebral hemorrhage is an unusual complication of autonomic hyperreflexia (AHR), which can be fatal if massive bleeding occurs with subsequent brain herniation. Episodes of AHR are most often triggered by bladder and rectal distention. We present a case of a 45-year-old quadriplegic male who suffered left basal ganglia and thalamic hemorrhage associated with AHR during surgery for pressure sore defects in the prone position under local anesthesia. Early recognition and removal of triggering factors of AHR failed to bring his blood pressure under control. The patient continued to deteriorate neurologically and died 9 days after the attack. A preventive measure rather than episodic treatment of AHR may be of paramount importance to avoid life-threatening complications, especially when a patient with a history of AHR is undergoing surgery in the prone position.
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Lee JK, Gollub LR. Second-order schedules with fixed-ratio components: variation of component size. J Exp Anal Behav 2010; 15:303-10. [PMID: 16811516 PMCID: PMC1333841 DOI: 10.1901/jeab.1971.15-303] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Key pecking by pigeons was reinforced with food under second-order schedules with fixed-ratio units. A constant total number of key pecks was required for reinforcement under each condition, but the size and, inversely, number of fixed-ratio components were varied. The total response requirement of 256 pecks was divided into fixed-ratio units of 128, 64, 32, 8, and 2 responses. A brief stimulus, which always preceded food reinforcement, was presented upon completion of each fixed-ratio unit. Under most conditions, the pattern of within-unit responding was typical of that under simple fixed-ratio schedules. Overall response rate was an inverted U-shaped function of component size. That is, response rates were highest under moderate sized units (fixed ratio 128 and 64). This relationship is consistent with previous determinations of rate as a function of fixed-ratio value for simple fixed-ratio schedules.
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Lee JK, Vadas P. An elusive case of systemic mastocytosis. Allergy Asthma Clin Immunol 2010. [PMCID: PMC2874294 DOI: 10.1186/1710-1492-6-s1-p24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Lee SB, Kang K, Pan C, Lee JK, Jung SH, Lee E, Nho CW. Gymnasterkoreayne B exerts chemopreventive effects through regulation of Nrf2 and p53 cooperatively. FASEB J 2010. [DOI: 10.1096/fasebj.24.1_supplement.720.6] [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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Liu JT, Liao WJ, Tan WC, Lee JK, Liu CH, Chen YH, Lin TB. Balloon kyphoplasty versus vertebroplasty for treatment of osteoporotic vertebral compression fracture: a prospective, comparative, and randomized clinical study. Osteoporos Int 2010; 21:359-64. [PMID: 19513578 DOI: 10.1007/s00198-009-0952-8] [Citation(s) in RCA: 170] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2009] [Accepted: 04/06/2009] [Indexed: 12/20/2022]
Abstract
UNLABELLED Bone pain and spinal axial deformity are major concerns in aged patients suffering from osteoporotic vertebral compression fracture (VCF). Pain can be relieved by vertebroplasty or kyphoplasty procedures, in which the compressed vertebral body is filled with substitutes. We randomly assigned 100 patients with osteoporotic compression fracture at the thoraco-lumbar (T-L) junction into two groups: vertebroplasty and kyphoplasty; we used polymethylmethacrylate (PMMA) as the bone filler. Pain before and after treatment was assessed with visual analog scale (VAS) scores and vertebral body height and kyphotic wedge angle were measured from reconstructed computed tomography images. More PMMA was used in the kyphoplasty group than in the vertebroplasty group (5.56 +/- 0.62 vs. 4.91 +/- 0.65 mL, p < 0.001). Vertebral body height and kyphotic wedge angle of the T-L spine were also improved (p < 0.001). VAS pain scores did not differ significantly between the treatment groups. The duration of follow-up was 6 months. Two patients in the kyphoplasty group had an adjacent segment fracture. In terms of clinical outcome there was little difference between the treatment groups. Thus, owing to the higher cost of the kyphotic balloon procedure, we recommend vertebroplasty over kyphoplasty for the treatment of osteoporotic VCFs. INTRODUCTION Spinal axial deformities are major concerns in aged patients suffering from osteoporotic vertebral compression fracture. Pain may be relieved by vertebroplasty or kyphoplasty. We investigated the radiological and clinical outcomes of these procedures. METHODS One hundred cases of VCF at the thoraco-lumbar junction were randomly assigned into two groups: vertebroplasty or kyphoplasty (50 cases each). We used polymethylmethacrylate as the bone filler. Pain before and after treatment was assessed with visual analog scale scores and vertebral body height and kyphotic wedge angle were measured from reconstructed computed tomography images. RESULTS More PMMA was used in the kyphoplasty group than in the vertebroplasty group (5.56 +/- 0.62 vs. 4.91 +/- 0.65 mL, p < 0.001). Vertebral body height and kyphotic wedge angle of the T-L spine were also improved (p < 0.001). VAS pain scores did not differ significantly between the treatment groups. The duration of follow-up was 6 months. Two patients in the kyphoplasty group had an adjacent segment fracture. CONCLUSIONS In terms of clinical outcome there was little difference between the treatment groups. Thus, with the higher cost of the kyphotic balloon procedure, we recommend vertebroplasty over kyphoplasty for the treatment of osteoporotic VCFs.
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Hwang JH, Song SH, Kim KA, Shin BK, Lee JK, Lee NW, Lee KW. Primary serous papillary carcinoma of the peritoneum mimicking pelvic actinomycosis: a case report and brief literature review. EUR J GYNAECOL ONCOL 2010; 31:214-216. [PMID: 20527245] [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
Primary serous papillary carcinoma of the peritoneum is a rare tumor, histologically similar to primary ovarian carcinoma. Pelvic CT and MRI are helpful to diagnose primary carcinoma of the peritoneum. We present a case of primary serous carcinoma of the peritoneum mimicking pelvic actinomycosis in a 59-year-old woman. Pelvic CT and MRI suggested pelvic actinomycosis. Exploratory laparotomy was performed to remove the mass and the diagnosis was confirmed by pathology. A subtotal hysterectomy, left salpingo-oophorectomy and omentectomy were performed. Histopathology examination revealed peritoneal carcinomatosis and primary serous carcinoma of the peritoneum. Pelvic CT and MRI were limited in their ability to differentiate inflammation, such as actinomycosis, from primary carcinoma of the peritoneum.
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Kim ES, Lee JK. Histone deacetylase inhibitors decrease the antigen presenting activity of murine bone marrow derived dendritic cells. Cell Immunol 2009; 262:52-7. [PMID: 20096829 DOI: 10.1016/j.cellimm.2009.12.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2009] [Accepted: 12/21/2009] [Indexed: 11/29/2022]
Abstract
Once activated by infected pathogens, dendritic cells (DCs) undergo activation and release inflammatory mediators responsible for the signs of inflammation. Our aim was to elucidate whether histone deacetylase inhibitors (HDACIs), trichostatine-A (TSA), scriptaid (ST) and sodium butylate (SB) regulate the inflammatory response of DCs. Pre-treatment with TSA and ST reduced the syngeneic and allogeneic-antigen presenting activity of LPS-stimulated DCs in a dose dependent manner to statistical significance. SB also reduced the antigen presenting activity of DCs, but not significantly. HDACIs mediate their effects through the modulation of DC maturation and pre-treatment of the DCs with TSA or ST prior to treatment with LPS reduced the expressions of DC mature markers to the level of immature dendritic cells (iDCs). Moreover, TSA and ST reduced the IL-2 production from LPS-stimulated mature DCs. Our results suggest that HDACIs may actively modulate the DC-induced inflammatory response through inhibition of phenotypical or functional maturation.
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Sim KS, Lee JK, Lai MA, Tso CP. Gaussian-Taylor signal-to-noise ratio estimation for scanning electron microscope images. J Microsc 2009; 236:18-34. [PMID: 19772533 DOI: 10.1111/j.1365-2818.2009.03194.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
A new and robust parameter estimation technique, named Gaussian-Taylor interpolation, is proposed to predict the signal-to-noise ratio (SNR) of scanning electron microscope images. The results of SNR and variance estimation values are tested and compared with piecewise cubic Hermite interpolation, quadratic spline interpolation, autoregressive moving average and moving average. Overall, the proposed estimations for noise-free peak and SNR are most consistent and accurate to within a certain acceptable degree compared with the others.
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Yoo KY, Lee MK, Jeong CW, Kim SJ, Jeong ST, Shin MH, Lee JK, Lee J. Anaesthetic requirement and stress hormone responses in patients undergoing lumbar spine surgery: anterior vs. posterior approach. Acta Anaesthesiol Scand 2009; 53:1012-7. [PMID: 19426236 DOI: 10.1111/j.1399-6576.2009.01993.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND The intensity of nociceptive stimuli reflects the severity of tissue injury. The anaesthetic requirement and stress hormonal responses were determined to learn whether they differ according to different surgical approaches (anterior vs. posterior) during the spinal surgery. METHODS Patients undergoing lumbar spine surgery without neurological deficits were divided into two groups: one having posterior (n=13) and the other having anterior fusion (n=13). The end-tidal sevoflurane concentrations (ET(SEVO)) required to maintain the bispectral index score at 40-50 were determined. Mean arterial pressure (MAP), heart rate (HR), central venous pressure (CVP), serum osmolality and plasma concentrations of catecholamines, cortisol and vasopressin (AVP) were measured. RESULTS There were no differences in MAP, HR, CVP and serum osmolality between the groups. ET(SEVO) was higher in the anterior than in the posterior group (P<0.05). The plasma concentrations of norepinephrine and cortisol increased in both groups during the surgery, whereas those of epinephrine remained unchanged. AVP concentrations increased during the surgery in the anterior group, and remained unaltered in the posterior group. The anterior group needed more analgesics (P<0.01) during the first 1 h after the operation. CONCLUSIONS The anterior approach required a deeper level of anaesthesia while undergoing spinal surgery and more use of post-operative analgesics than the posterior approach. It was also associated with a more pronounced AVP release during the surgery.
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Kim IY, Kim SH, Kim JH, Lee JK. Rapid spontaneous resolution of a traumatic cervical epidural haematoma. Br J Neurosurg 2009; 19:451-2. [PMID: 16455573 DOI: 10.1080/02688690500390524] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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Kwon Y, Lee JK, Sung JK, Lee JH, Kim SJ, Shin YS, Park K. Synthesis and photoluminescence properties of spherical fine red (Y(1-x-y)Gd(x)EU(y))BO3 (0 < or = x < or = 0.36, 0.06 < or = y < or = 0.13) phosphors using ultrasonic spray pyrolysis. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2009; 9:4202-4206. [PMID: 19916430 DOI: 10.1166/jnn.2009.m32] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The post-heat treated (Y(1-x-y)Gd(x)Eu(y))BO3 (0 < or = x < or = 0.36, 0.06 < or = y < or = 0.13) powders crystallized in a solution of (Y(1-x-y)Gd(x)Eu(y))BO3 with the hexagonal vaterite crystal structure, irrespective of composition. The lattice parameter of the (Y(0.9-x)Gd(x)Eu(0.1))BO3 (0 < or = x < or = 0.36) powders slightly increased with an increase in Gd content. The average powder sizes were sub-micron order and the powders showed relatively uniform size distribution and smooth surface. We obtained improved powder morphologies by adding organic additives such as ethylene glycol and citric acid. For the post-treated (Y(0.9-x)Gd(x)Eu(0.1))BO3, the emission intensity became stronger with increasing Gd content up to x = 0.27. In addition, for the post-treated (Y(0.73-y)Gd(0.27)Eu(y))BO3, the emission intensity gradually increased with Eu content up to y = 0.13. In particular, the emission intensity of the (Y(0.6)Gd)0.27)Eu(0.13))BO3 powders synthesized was higher than that of the commercial (Y,Gd)BO3:Eu3+ product.
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Kim BJ, Lee KT, Moon TG, Kang P, Lee JK, Kim JJ, Rhee JC. How do we interpret an elevated carbohydrate antigen 19-9 level in asymptomatic subjects? Dig Liver Dis 2009; 41:364-9. [PMID: 19162573 DOI: 10.1016/j.dld.2008.12.094] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2008] [Revised: 11/25/2008] [Accepted: 12/03/2008] [Indexed: 12/11/2022]
Abstract
AIM This prospective cohort study aimed to evaluate the etiology of elevated CA 19-9 levels and to present appropriate guidelines for the asymptomatic patients. METHODS Between January 2004 and March 2007, we enrolled consecutive asymptomatic patients who had elevated CA 19-9 levels >37 U/mL. To evaluate the etiology, the CA 19-9 level was rechecked and further studies were carried out. If the CA 19-9 level decreased to the normal range, or if it showed a decreasing trend, then it was monitored annually. Yet, if the CA 19-9 level showed an increasing trend, then the level was monitored at intervals of 1, 3, and 6 months until no evidence of malignancy was proven. RESULTS Of the 62,976 patients, 501 (0.8%) subjects showed an elevated CA 19-9 level. This prospective analysis was conducted on 353 subjects (70.5%) who were followed up for at least 6 months. Ten patients (2.8%) were diagnosed with malignancies. There were 97 patients (27.5%) with benign diseases and 246 patients (69.7%) were deemed non-specific. CONCLUSIONS CA 19-9 should not be used as a screening tool. In the case of a persistently elevated CA 19-9 level, further work-up for determining the etiology should be done.
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Kim DS, Kim JH, Kwon Lee J, Choi SJ, Kim JS, Jeun SS, Oh W, Yang YS, Chang JW. Overexpression of CXC Chemokine Receptors Is Required for the Superior Glioma-Tracking Property of Umbilical Cord Blood-Derived Mesenchymal Stem Cells. Stem Cells Dev 2009; 18:511-9. [DOI: 10.1089/scd.2008.0050] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
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Phillips P, Lee JK, Wang C, Yoshida E, Lima VD, Montaner J. Chylous ascites: a late complication of intra-abdominal Mycobacterium avium complex immune reconstitution syndrome in HIV-infected patients. Int J STD AIDS 2009; 20:285-7. [DOI: 10.1258/ijsa.2008.008275] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Chylous ascites related to Mycobacterium avium complex (MAC) in HIV-infected patients is rare, with only six cases reported in the English literature. We report a series of six cases from a single institution. During the past six years, chylous ascites was diagnosed in six (35%) of 17 AIDS patients, all of whom had previously been diagnosed with intra-abdominal MAC immune reconstitution syndrome (MAC-IRS). A review of medical records identified no other cases of chylous ascites among HIV-positive patients over the past 13 years (1994–2007), and the incidence was estimated at one in 2248 HIV-positive admissions. The ascitic fluid had a milky appearance and a median triglyceride level of 4.07 mmol/L (range 3.19–29.6 mmol/L) (360 mg/dL, range 282–2620 mg/dL). After a median follow-up of 20 months, five (83%) of six patients survived. Chylous ascites is a late complication of intra-abdominal MAC-IRS, and is usually associated with a favourable prognosis.
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Lee JK, Lee YR, Lee YH, Kim K, Lee CK. Production of TGF-beta1 as a Mechanism for Defective Antigen-presenting Cell Function of Macrophages Generated in vitro with M-CSF. Immune Netw 2009; 9:27-33. [PMID: 20107535 PMCID: PMC2803298 DOI: 10.4110/in.2009.9.1.27] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2008] [Revised: 12/19/2008] [Accepted: 12/24/2008] [Indexed: 12/03/2022] Open
Abstract
Background Macrophages generated in vitro using macrophage-colony stimulating factor (M-CSF) and interleukin (IL)-6 from bone marrow cells (BM-Mp) are defective in antigen presenting cell (APC) function as shown by their ability to induce the proliferation of anti-CD3 mAb-primed syngeneic T cells. However, they do express major histocompatibility (MHC) class I and II molecules, accessory molecules and intracellular adhesion molecules. Here we demonstrate that the defective APC function of macrophages is mainly due to production of TGF-β1 by BM-Mp. Methods Microarray analysis showed that TGF-β1 was highly expressed in BM-Mp, compared to a macrophage cell line, B6D, which exerted efficient APC function. Production of TGF-β1 by BM-Mp was confirmed by neutralization experiments of TGF-β1 as well as by real time-polymerase chain reaction (PCR). Results Addition of anti-TGF-β1 monoclonal antibody to cultures of BM-Mp and anti-CD3 mAb-primed syngeneic T cells efficiently induced the proliferation of syngeneic T cells. Conversely, the APC function of B6D cells was almost completely suppressed by addition of TGF-β1. Quantitative real time-PCR analysis also confirmed the enhanced expression of TGF-β1 in BM-Mp. Conclusion The defective APC function of macrophages generated in vitro with M-CSF and IL-6 was mainly due to the production of TGF-β1 by macrophages.
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Park K, Lee JK, Kwon Y, Kim SJ, Nahm S. Luminescence properties of Ca(Y(0.915-x)Gd(x)Al0.025Eu0.06)BO4 phosphors under VUV irradiation. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2008; 8:5503-5505. [PMID: 19198486 DOI: 10.1166/jnn.2008.1215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The major phase of post-treated Ca(Y(0.915-x)Gd(x)A10.025Eu0.06)BO4 (0 < or = x < or = 0.3) phosphors was solid solutions of the constituent oxides, which had an orthorhombic warwickite-like structure. The calculated crystallite size of the Ca(Y(0.915-x)Gd(x)Al0.025Eu0.06)BO4 phosphors was approximately 36 nm. The Gd additive significantly enhanced both the charge transfer (CT) transition of O2(-) -Eu3+ and the absorption of the host materials, thereby resulting in an increase in emission intensity. The Ca(Y(0.715)Gd0.2Al0.025Eu0.06)BO4 phosphor showed the highest emission intensity at 593 nm, which was over five times as strong as that of a Gd-free Ca(Y0.915Al0.025Eu0.06)BO4 phosphor. The addition of Gd was desirable for improving the photoluminescent properties of red-emitting Ca(Y0.915Al0.025Eu0.06)BO4 phosphors.
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Kwon Y, Lee JK, Kim SJ, Nahm S, Park K. Photoluminescent properties of (la(1-x)Y(x))(0.94)Tb(0.06)PO4 phosphor powders prepared by ultrasonic spray pyrolysis. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2008; 8:5499-5502. [PMID: 19198485 DOI: 10.1166/jnn.2008.1211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The calculated crystallite sizes of (La(1-x)Y(x))(0.94)Tb(0.06)PO4 (0 < or = x < or = 1.0) phosphors ranged from 37-39 nm. Annealed (La(1-x)Y(x))(0.94)Tb(0.06)PO4 (0 < or = x < or = 1.0) phosphors showed a smooth, regular, and spherical morphology. Strong excitation peaks were appeared at 226 and 270 nm for all the phosphors. These were caused by the crystal splitting of 7D and 9D of 4f75d1 configuration in Tb3+, respectively. The characteristic emission peaks were observed at 489, 543, 585, and 621 nm, which were caused by the 5D4-7F(j) (j = 6-3) transitions of Tb3+, respectively. The emission intensity at 543 nm increased with an increase in Y content up to 0.5 and then decreased for a higher Y content.
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Chelvarajah R, Lee JK, Chandrasekaran S, Bavetta S. A clinical audit of neurosurgical bed usage. Br J Neurosurg 2008; 21:610-3; discussion 614-5. [PMID: 18071990 DOI: 10.1080/02688690701649488] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
AIM To investigate inefficiencies during patients' stay in neurosurgical beds. METHODS A prospective audit of neurosurgical inpatients was conducted over approximately 2 months. We recorded the causes and duration of inappropriate delays, defined as actions requiring more that 24 h from initiation until completion. RESULTS One-hundred-and-thirty-eight patients were studied (61 elective and 77 emergency admissions). The audited patients were in hospital for a total of 1665 days. Of these, 482 days (29%) were due to delays. 92.5% of these wasted days involved emergency admissions. The main categories of delay were transfer back to referring hospital (46% of all delays), operative (26%) and radiological (19%). Our own hospital was responsible for the longest transfer delays (6.3 days/patient compared with an average of 2.8 for all hospitals). Operative waits arose because of problems with both the timing and capacity of lists. Radiological delays resulted in particular from waits for MRI scans and neuroradiologist-performed procedures. The effect of eliminating all these inappropriate delays would be equivalent to liberating 10.7 of our 37 neurosurgical beds at any one time. CONCLUSIONS Clinician-led analysis of organizational aspects of patient care has revealed serious structure, process and capacity problems in efficient bed usage, We have made proposals to address the cause of the inappropriate delays.
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Triffo WJ, Palsdottir H, McDonald KL, Lee JK, Inman JL, Bissell MJ, Raphael RM, Auer M. Controlled microaspiration for high-pressure freezing: a new method for ultrastructural preservation of fragile and sparse tissues for TEM and electron tomography. J Microsc 2008; 230:278-87. [PMID: 18445158 PMCID: PMC2734140 DOI: 10.1111/j.1365-2818.2008.01986.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
High-pressure freezing is the preferred method to prepare thick biological specimens for ultrastructural studies. However, the advantages obtained by this method often prove unattainable for samples that are difficult to handle during the freezing and substitution protocols. Delicate and sparse samples are difficult to manipulate and maintain intact throughout the sequence of freezing, infiltration, embedding and final orientation for sectioning and subsequent transmission electron microscopy. An established approach to surmount these difficulties is the use of cellulose microdialysis tubing to transport the sample. With an inner diameter of 200 microm, the tubing protects small and fragile samples within the thickness constraints of high-pressure freezing, and the tube ends can be sealed to avoid loss of sample. Importantly, the transparency of the tubing allows optical study of the specimen at different steps in the process. Here, we describe the use of a micromanipulator and microinjection apparatus to handle and position delicate specimens within the tubing. We report two biologically significant examples that benefit from this approach, 3D cultures of mammary epithelial cells and cochlear outer hair cells. We illustrate the potential for correlative light and electron microscopy as well as electron tomography.
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MESH Headings
- Animals
- Biopsy, Fine-Needle
- Cells, Cultured
- Dialysis
- Epithelial Cells/ultrastructure
- Freeze Substitution
- Freezing
- Guinea Pigs
- Hair Cells, Auditory, Outer/cytology
- Hair Cells, Auditory, Outer/ultrastructure
- Mammary Glands, Animal/cytology
- Mammary Glands, Animal/growth & development
- Mice
- Micromanipulation
- Microscopy, Electron, Transmission/methods
- Organ Culture Techniques
- Pressure
- Tomography/methods
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Yoon KS, Min KJ, Jung YJ, Kwon KY, Lee JK, Oh SW. A model of the effect of temperature on the growth of pathogenic and nonpathogenic Vibrio parahaemolyticus isolated from oysters in Korea. Food Microbiol 2008; 25:635-41. [PMID: 18541160 DOI: 10.1016/j.fm.2008.04.007] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2008] [Revised: 04/16/2008] [Accepted: 04/17/2008] [Indexed: 10/22/2022]
Abstract
Vibrio parahaemolyticus is recognized as the leading cause of human gastroenteritis associated with the consumption of seafood. The objective of this study was to model the growth kinetics of pathogenic and nonpathogenic V. parahaemolyticus in broth and oyster slurry. Primary growth models of V. parahaemolyticus in broth and oyster slurry fit well to a modified Gomperz equation (broth R(2)=0.99; oyster slurry R(2)=0.96). The lag time (LT), specific growth rate (SGR), and maximum population density (MPD) of each primary model were compared. The growth of nonpathogenic V. parahaemolyticus was found to be more rapid than that of pathogenic V. parahaemolyticus, regardless of the model medium. In addition, significant (P<0.05) differences in the growth kinetics between pathogenic and nonpathogenic V. parahaemolyticus in broth were observed at 10 degrees C. When compared to growth in broth, the growth of V. parahaemolyticus was delayed in oyster slurry, and growth was not observed at 10 or 15 degrees C. The Davey and square root models were identified as appropriate secondary models for predicting the LT and SGR, respectively. For the broth model, the average B(f) and A(f) values for LT were found to be 0.97 and 1.3, respectively, whereas the average B(f) and A(f) values for SGR were 1.05 and 1.11, respectively. The model generated in this study predicted an LT that was shorter and an SGR that was similar to those that were actually observed, which indicates that these models provide a reliable and safe prediction of V. parahaemolyticus growth.
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Lee JK, Lee MK, Jin HJ, Kim DS, Yang YS, Oh W, Yang SE, Park TS, Lee SY, Kim BS, Jeun SS. Efficient intracytoplasmic labeling of human umbilical cord blood mesenchymal stromal cells with ferumoxides. Cell Transplant 2008; 16:849-57. [PMID: 18088004 DOI: 10.3727/000000007783465271] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Mesenchymal stromal cells (MSCs) are multipotent cells found in several adult tissues; they have the capacity to differentiate into mesodermal, ectodermal, and endodermal tissues in vitro. There have been several reports that MSCs have therapeutic effects in a variety of diseases. Therefore, using a cell labeling technique, monitoring their temporal and spatial migration in vivo, would be useful in the clinical setting. Magnetic resonance imaging (MRI)--tracking of superparamagnetic iron oxide (SPIO)-labeled cells--is a noninvasive technique for determining the location and migration of transplanted cells. In the present study, we evaluated the influence and toxicity of SPIO (ferumoxides) labeling on multiple differentiated MSCs. To evaluate the influence and toxicity of ferumoxides labeling on differentiation of MSCs, a variety of concentrations of ferumoxides were used for labeling MSCs. We found that the cytoplasm of adherent cells was effectively labeled at low concentrations of ferumoxides. Compared with unlabeled controls, the ferumoxides-labeled MSCs exhibited a similar proliferation rate and apoptotic progression. The labeled MSCs differentiated into osteoblasts and adipocytes in an identical fashion as the unlabeled cells. However, chondrogenesis and neurogenesis were inhibited at high concentrations of ferumoxides. Our results suggest the effective concentration for ferumoxides use in tracking MSCs.
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Pan C, Kim ES, Jung SH, Lee JK. Immunosuppressive effect of tectorigenine on mouse macrophage cell line. FASEB J 2008. [DOI: 10.1096/fasebj.22.2_supplement.335] [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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125
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JU JUNGHUN, Lee JK, Sohn KH, Lee JP, Kim JH, Lim CH, Hong SK, Kim IY, Kim JR, Ock SW, Kim SH, Park KL. Immune related gene expression profiling of UVB‐induced photoaging skin in SKH‐1 hairless mice. FASEB J 2008. [DOI: 10.1096/fasebj.22.2_supplement.414] [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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