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Koochekpour S, Lee TJ, Sun Y, Hu S, Grabowski GA, Liu Z, Garay J. Prosaposin is an AR-target gene and its neurotrophic domain upregulates AR expression and activity in prostate stromal cells. J Cell Biochem 2008; 104:2272-85. [PMID: 18481277 DOI: 10.1002/jcb.21786] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Recent studies have introduced prosaposin (PSAP) as a pleiotrophic growth factor for prostate cancer (PCa). We have previously reported that PSAP or one of its known active molecular derivatives, saposin C functions as an androgen-agonist and androgen-regulated gene (ARG) for androgen-sensitive (AS) PCa cell lines. Due to the potential significance of androgen receptor (AR)-expressing stroma in PCa, we evaluated a possible bi-directional paracrine regulatory interactions between DHT and PSAP in AR-positive prostate stromal (PrSt) cells. We report that saposin C in a ligand-independent manner increased AR expression, its nuclear content, and tyrosine phosphorylation. DHT treatment of PrSt cells increased PSAP expression. We also demonstrated both serum- and androgen-inducibility of a previously characterized hormone-responsive element (HRE) located in the proximal region of PSAP promoter. In addition, conditioned-media derived from PrSt cells and bone fibroblasts (i.e., MSF) differentially increased PSAP-promoter activity in androgen-independent (AI) PC-3 and AS LNCaP cells. Our data for the first time demonstrate that not only saposin C or PSAP regulates AR expression/activity, but also function as an ARG in PrSt. Ligand-independent activation of AR by PSAP or saposin C in PCa and stromal cells may contribute not only to prostate carcinogenesis at an early stage, but also in AI progression of the disease in an androgen-deprived tumor microenvironment.
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Chun JK, Lee TJ, Choi KM, Lee KH, Kim DS. Elevated anti-alpha-enolase antibody levels in Kawasaki disease. Scand J Rheumatol 2008; 37:48-52. [PMID: 18189195 DOI: 10.1080/03009740701607075] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
OBJECTIVE By functioning as a heat-shock protein (HSP), alpha-enolase has an important role in the pathophysiology of multivariant vasculitis. Kawasaki disease (KD) is a type of vasculitis occurring primarily in children. The role of alpha-enolase in KD was assessed by measuring anti-alpha-enolase antibody (Ab) titres in patients with KD and the usefulness of anti-alpha-enolase Ab as a diagnostic tool in atypical KD patients was evaluated. METHODS Anti-alpha-enolase Ab titres were measured by using an enzyme-linked immunosorbent assay (ELISA) in seven normal control patients, nine febrile control patients and 14 KD patients (10 typical KD, four atypical KD). A standard deviation (SD) of 3 above the mean of the normal control group was considered to be positive reactivity. Western blotting using recombinant human alpha-enolase was performed in four KD patients and three normal controls. RESULTS With the positive reactivity limited to +3 SD over the mean (>0.6), 10 out of 14 patients (71%) were positive at the acute onset and 12 out of 14 patients (85.7%) were positive before discharge. In total, 12 out of 14 patients (85.7%) were positive either at acute onset or before discharge. All four atypical KD patients showed positive reactivity. Specific positive bands against recombinant human alpha-enolase were detected by western blotting in all four KD patients, but no reactivity was seen in three patients with normal controls. CONCLUSION This is the first study to demonstrate that autoantibodies against the alpha-enolase are present in the sera of KD patients. We suggest that anti-alpha-enolase Ab should be a good candidate for a diagnostic tool in atypical KD.
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Koochekpour S, Lee TJ, Wang R, Sun Y, Delorme N, Hiraiwa M, Grabowski GA, Culig Z, Minokadeh A. Prosaposin is a novel androgen-regulated gene in prostate cancer cell line LNCaP. J Cell Biochem 2007; 101:631-41. [PMID: 17171640 DOI: 10.1002/jcb.21207] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Androgen-regulated genes (ARG) are implicated in normal and neoplastic growth of the prostate. Recently, we reported genomic amplification and/or overexpression of a previously known neurotrophic factor, prosaposin, in androgen-independent (AI) or metastatic prostate cancer (PCa) cells and tissues. Prosaposin and/or its known active molecular derivatives (e.g., saposin C) function as a pluripotent growth factor with diverse biological activities that favor malignant phenotypes in PCa cells. In addition, prosaposin or saposin C upregulates androgen receptor (AR) and AR-target genes (i.e., prostate-specific antigen, Probasin) expression and activity in LNCaP cells. Here, we examined prosaposin as an ARG. We report that DHT treatment of LNCaP cells increases prosaposin expression. In addition, we demonstrate androgen-responsiveness of prosaposin promoter and AR occupancy to a hormone-responsive element located in the proximal region of the prosaposin promoter. Our data for the first time identify prosaposin as an ARG. This observation, together with the pleiotropic growth factor activity of prosaposin, might suggest a role for this molecule in AR-dependent progression of prostate cancer at its early or late AI-state.
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Lee TJ, Chun JK, Yeon SI, Shin JS, Kim DS. Increased serum levels of macrophage migration inhibitory factor in patients with Kawasaki disease. Scand J Rheumatol 2007; 36:222-5. [PMID: 17657678 DOI: 10.1080/03009740701218790] [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: 01/15/2023]
Abstract
OBJECTIVE To determine whether serum levels of macrophage migration inhibitory factor (MIF) increase in patients with Kawasaki disease (KD) and also correlate with other inflammatory indices. METHODS Serum samples from 10 patients with KD, 15 normal healthy subjects, and seven febrile control subjects were assayed for MIF by enzyme-linked immunosorbent assay (ELISA). RESULTS There was a significant increase in the serum levels of MIF in the acute stage of KD [113.06 (range 20.6-157.36) ng/mL] compared with those in the subacute stage [28.11 (8.57-143.48) ng/mL, p<0.01], normal controls [12.95 (8.40-18.67) ng/mL, p<0.001], and febrile controls [36.58 (21.31-59.67) ng/mL, p = 0.01]. The increase in MIF correlated with an increase in interleukin-6 (IL-6) (r = 0.52, p = 0.047). CONCLUSION MIF may be a useful marker in the acute stage of KD and may provide important clues to the pathogenesis of this disease.
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Park JH, Lee SB, Lee TJ, Lee DY, Jhoo JH, Youn JC, Choo IH, Choi EA, Jeong JW, Choe JY, Woo JI, Kim KW. Depression in vascular dementia is quantitatively and qualitatively different from depression in Alzheimer's disease. Dement Geriatr Cogn Disord 2007; 23:67-73. [PMID: 17114882 DOI: 10.1159/000097039] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/20/2006] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND/AIMS To compare the prevalence and characteristics of depression in vascular dementia (VaD) and Alzheimer's disease (AD) after adjusting for dementia severity and gender. METHODS One hundred and eight pairs of VaD and AD patients matched for dementia severity and gender were assessed. RESULTS Major depressive disorder (MDD) was more prevalent in the VaD group than in the AD group (20.4% in VaD, 10.2% in AD, p = 0.04, Cochran-Mantel-Haenszel, CMH, test) regardless of the dementia severity and gender. The odds ratio for developing MDD in the VaD group versus the AD group was estimated to be 2.20 (95% confidence interval = 1.02-4.74). Neurovegetative symptoms such as 'felt tired and weak all the time' (30.6% in VaD, 13.9% in AD, p = 0.003, CMH test) and 'changed weight without trying' (16.7% in VaD, 6.5% in AD, p = 0.02, CMH test) were more prevalent in the VaD group than in the AD group. CONCLUSION Depression in VaD was quantitatively and qualitatively different from that in AD regardless of the severity of dementia and gender; depression was more prevalent, severer and more retarded and vegetative in VaD than in AD.
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Pandolfino JE, Lee TJ, Schreiner MA, Zhang Q, Roth MP, Kahrilas PJ. Comparison of esophageal acid exposure at 1 cm and 6 cm above the squamocolumnar junction using the Bravo pH monitoring system. Dis Esophagus 2006; 19:177-82. [PMID: 16722995 DOI: 10.1111/j.1442-2050.2006.00561.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The aim of this study was to assess the quantitative differences of acid exposure at 1 cm and 6 cm above the squamocolumnar junction (SCJ) using two radiotelemetry pH capsules affixed to the esophageal mucosa. Ten normal subjects and 10 endoscopy-negative gastroesophageal reflux disease (GERD) patients without hiatus hernia (ages 20-54, 12 male) were studied for a 24-h period using the Bravo pH monitoring system. pH capsules were placed 1 cm and 6 cm above the SCJ. Interpretable data for at least 14 h was obtained in 18 of the 20 subjects (9 normal, 9 GERD). Two failures occurred secondary to early capsule dislodgement. Median esophageal acid exposure was significantly increased at 1 cm above the SCJ compared to 6 cm above the SCJ during the total, upright and postprandial time periods in both normal and GERD subjects. During a 2 h postprandial period the esophageal acid exposure was 8-fold greater in GERD subjects and 5-fold greater in normal subjects 1 cm above the SCJ compared to 6 cm above the SCJ. Confident measurement of esophageal acid exposure at a fixed position 1 cm above the SCJ is feasible with the Bravo system. Acid exposure was significantly higher 1 cm above the SCJ compared to 6 cm above the SCJ in both GERD patients and controls. These findings suggest that measurement of acid exposure 1 cm above the SCJ may improve accuracy of pH monitoring by detecting acid reflux events confined to the distal esophagus.
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Lam MZC, Lee TJ, Boey PY, Ng WF, Hey HW, Ho KY, Cheong PY. Factors influencing cardiac auscultation proficiency in physician trainees. Singapore Med J 2005; 46:11-4. [PMID: 15633002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Abstract
INTRODUCTION We assessed the accuracy of physician trainees in identifying different cardiac sounds and examined the factors influencing their cardiac auscultation proficiency. METHODS A total of 106 physicians in the Family Medicine Training Programme were asked to identify 10 cardiac sounds played sequentially on the Littmann electronic stethoscope, which functioned as a surrogate patient. Their auscultation accuracy was scored numerically out of a maximum of 10. Demographical data of the physicians was collected prospectively. RESULTS The mean (+/-SD) auscultation proficiency score of the study population was 4.0 +/- 1.7. Physicians who graduated in 1994 or earlier fared significantly poorer than those who obtained their Bachelor of Medicine and Bachelor of Surgery degrees between 1995 and 2000 (p-value equals 0.02). Auscultation proficiency was not related to current practice, previous years of primary care, cardiology, internal medicine or paediatric medicine postings, or cumulative years of postings. Normal heart sounds were most accurately identified. Prosthetic cardiac sounds were better identified than other extra-cardiac sounds while systolic murmurs were more accurately identified than diastolic murmurs. Tachycardia had the lowest identification rate. CONCLUSION Our data suggest that cardiac auscultation skill declined with time, being significantly impaired eight years after graduation. We suggest that there is a need for retraining in the form of continuing medical education to address not only new knowledge and skills, but also basic skill competency.
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Lee TJ, Fennerty MB, Howden CW. Systematic review: Is there excessive use of proton pump inhibitors in gastro-oesophageal reflux disease? Aliment Pharmacol Ther 2004; 20:1241-51. [PMID: 15606386 DOI: 10.1111/j.1365-2036.2004.02289.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND Proton-pump inhibitors are often recommended for continuous use in gastro-oesophageal reflux disease, but this may not be necessary in all patients. AIM To ascertain the level of evidence for alternative strategies for proton-pump inhibitor treatment in gastro-oesophageal reflux disease. METHODS We searched for observational or interventional studies examining alternatives to continuous proton-pump inhibitor treatment in gastro-oesophageal reflux disease. RESULTS Non-randomized studies suggest that some patients with gastro-oesophageal reflux disease, including some with erosive oesophagitis, may be adequately maintained on proton-pump inhibitor therapy given less frequently than once daily. However, the results may not be generalizable. Four high quality randomized-controlled trials compared 'on-demand' proton-pump inhibitor and placebo treatment in endoscopy-negative reflux disease; all found this effective for most patients. One high quality randomized-controlled trial found intermittent courses of a proton-pump inhibitor or H2-receptor antagonist in erosive oesophagitis or endoscopy-negative reflux disease adequate for almost half of the patients studied. Up to 80% of patients on continuous high-dose proton-pump inhibitor treatment for gastro-oesophageal reflux disease can be 'stepped down' to less intensive therapy. CONCLUSIONS On-demand proton-pump inhibitor treatment may be appropriate in endoscopy-negative reflux disease. In gastro-oesophageal reflux disease, patients taking more than once daily or high-dose proton-pump inhibitor treatment, a step down to once daily or standard dose therapy should be attempted.
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Nakano K, Iwasawa H, Ito O, Lee TJ, Matsumura M. Improved simultaneous nitrification and denitrification in a single reactor by using two different immobilization carriers with specific oxygen transfer characteristics. Bioprocess Biosyst Eng 2004; 26:141-5. [PMID: 14872334 DOI: 10.1007/s00449-003-0345-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2002] [Accepted: 12/09/2003] [Indexed: 10/26/2022]
Abstract
To maximize nitrogen utilization rates during nitrification and denitrification in a simultaneous reaction for direct nitrogen removal from ammonia-nitrogen in a single reactor, two different carriers were applied that immobilized nitrifiers and denitrifiers separately. With the optimized DO concentration and mixing ratio of immobilization carriers, ammonium-nitrogen was successfully removed as designed until the middle phase of treatment where nitrogen removal rate was higher than 83% of the theoretical value, although an imbalance between nitrification and denitrification occurred at a later phase of treatment where residual nitrate-nitrogen concentration was less than 2 mg/l. The new approach using two different carriers to immobilize nitrifiers and denitrifiers separately was proved useful for controlling both nitrification and denitrification rates, enabling the utilization of maximum treatment ability of both nitrifiers and denitrifiers in a single reactor for direct nitrogen removal from ammonium-nitrogen.
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Lyu SC, Lee TJ, Yang CW, Lee CJ. Synthesis and characterization of high-quality double-walled carbon nanotubes by catalytic decomposition of alcohol. Chem Commun (Camb) 2003:1404-5. [PMID: 12841263 DOI: 10.1039/b302322b] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report the synthesis of high-quality double-walled carbon nanotubes without defects by catalytic decomposition of alcohol over an Fe-Mo/Al2O3 catalyst; the synthesized DWNTs have outer diameters in the range of 1.52-3.54 nm and an average interlayer distance of 0.38 nm between graphene layers.
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Lyu SC, Liu BC, Lee TJ, Liu ZY, Yang CW, Park CY, Lee CJ. Synthesis of high-quality single-walled carbon nanotubes by catalytic decomposition of C2H2. Chem Commun (Camb) 2003:734-5. [PMID: 12703797 DOI: 10.1039/b300109a] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
High-quality single-walled carbon nanotubes free of defects and amorphous carbon coating have been produced by catalytic decomposition of C2H2 over Fe-Mo/Al2O3 catalyst.
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Lee TJ, Kawaharasaki M, Matsumura M, Nakamura K. Microbial community structures of activated sludges dominated with polyphosphate-accumulating bacteria and glycogen-accumulating bacteria. ENVIRONMENTAL TECHNOLOGY 2002; 23:747-755. [PMID: 12164636 DOI: 10.1080/09593332308618371] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The microbial community structures of anaerobic-aerobic activated sludges, which are dominated with polyphosphate-accumulating bacteria (PABs) and glycogen-accumulating bacteria (GABs), were investigated by quinone profile method and dual staining DAPI (4',6-diamidino-2-phenylindol dihydrochloride) with fluorescent in situ hybridization (FISH). For both activated sludges, the predominant bacterial groups were the beta subclass of the Proteobacteria that contained mainly Q-8 as analyzed by the quinone profile method and gram-positive bacteria with a high DNA G+C content based on FISH. A 16S rRNA-targeted oligonucleotide probe (MP2) specific for M. phosphovorus, a known polyphosphate-accumulating bacterium, was also applied to PABs and GABs-enriched activated sludge to evaluate their possible role in the enhanced biological phosphorus removal (EBPR) process. Interestingly, the bacteria that hybridized with the probe specific to M. phosphovorus in the sludge dominated with PABs represent about 6.9% of the total microorganisms. In the sludge dominated with GABs, these bacteria were about 1.9%. These results suggest its possible involvement in the EBPR process.
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Blott BH, Lee TJ. A two frequency vibrating capacitor method for contact potential difference measurements. ACTA ACUST UNITED AC 2002. [DOI: 10.1088/0022-3735/2/9/307] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Lee TJ, Blott BH, Hopkins BJ. The work function variation during caesium deposition on the (100) and (110) single crystal surfaces of tungsten. ACTA ACUST UNITED AC 2002. [DOI: 10.1088/0305-4608/1/3/312] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Lee TJ, Nakano K, Matsumura M. A novel strategy for cyanobacterial bloom control by ultrasonic irradiation. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2002; 46:207-215. [PMID: 12380993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The application of ultrasonic irradiation to control cyanobacterial blooms was evaluated in actual eutrophic lake water. Ten prototype units of the Ultrasonic Irradiation System (USIS) were installed in the 32 ha Lake Senba, and the water and sediment quality were monitored for 2 years. By incorporating the ultrasonication process with the on-going strategy, particularly flushing with induction water, cyanobacterial blooms can be controlled effectively. In addition, a significant improvement in the conditions of the lake in terms of chlorophyll-a, COD and T-P was attained. Moreover, the feasibility of ultrasonic irradiation and bacterial assisted control of cyanobacterial blooms was also evaluated in laboratory conditions. The destruction of gas vacuoles brought about by ultrasonic irradiation promoted close contact between cyanobacteria and their lysing Myxobacter leading to immediate and accelerated destruction of the cells.
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Nakano K, Lee TJ, Matsumura M. In situ algal bloom control by the integration of ultrasonic radiation and jet circulation to flushing. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2001; 35:4941-4946. [PMID: 11775176 DOI: 10.1021/es010711c] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A novel strategy for in situ water bloom control was applied and evaluated in Lake Senba. The proposed strategy was to integrate ultrasonic radiation and water jet circulation to an existing flushing process for reducing the growth rate of cyanobacteria and to support the flushing process by providing efficient mixing. Ten units of the system, each consisting of an ultrasonication module and a water jet circulator module, were strategically situated on the lake, and the performance was monitored for 2 years. Water bloom occurrence reflected as chlorophyll a, SS, and transparency were controlled to lower levels when the integrated system was coupled with sufficient inflow water supply to achieve the target flushing rate. Also, an improvement in the water quality such as COD and phosphorus were observed. Based on linear regression analysis, relationships between water quality parameters and inflow water volume were discussed to evaluate the proposed strategy. Of the three major water quality parameters associated with water bloom, the integrated system contributed mainly to the reduction in SS and transparency compared to chlorophyll a reduction. Improved chlorophyll a reduction may be achieved by strategies that augment effective washout of cyanobacteria during flushing.
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Chen YC, Shen SC, Lee WR, Hou WC, Yang LL, Lee TJ. Inhibition of nitric oxide synthase inhibitors and lipopolysaccharide induced inducible NOS and cyclooxygenase-2 gene expressions by rutin, quercetin, and quercetin pentaacetate in RAW 264.7 macrophages. J Cell Biochem 2001; 82:537-48. [PMID: 11500931 DOI: 10.1002/jcb.1184] [Citation(s) in RCA: 171] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Several natural flavonoids have been demonstrated to perform some beneficial biological activities, however, higher-effective concentrations and poor-absorptive efficacy in body of flavonoids blocked their practical applications. In the present study, we provided evidences to demonstrate that flavonoids rutin, quercetin, and its acetylated product quercetin pentaacetate were able to be used with nitric oxide synthase (NOS) inhibitors (N-nitro-L-arginine (NLA) or N-nitro-L-arginine methyl ester (L-NAME)) in treatment of lipopolysaccharide (LPS) induced nitric oxide (NO) and prostaglandin E2 (PGE2) productions, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) gene expressions in a mouse macrophage cell line (RAW 264.7). The results showed that rutin, quercetin, and quercetin pentaacetate-inhibited LPS-induced NO production in a concentration-dependent manner without obvious cytotoxic effect on cells by MTT assay using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide as an indicator. Decrease of NO production by flavonoids was consistent with the inhibition on LPS-induced iNOS gene expression by western blotting. However, these compounds were unable to block iNOS enzyme activity by direct and indirect measurement on iNOS enzyme activity. Quercetin pentaacetate showed the obvious inhibition on LPS-induced PGE2 production and COX-2 gene expression and the inhibition was not result of suppression on COX-2 enzyme activity. Previous study demonstrated that decrease of NO production by L-arginine analogs effectively stimulated LPS-induced iNOS gene expression, and proposed that stimulatory effects on iNOS protein by NOS inhibitors might be harmful in treating sepsis. In this study, NLA or L-NAME treatment stimulated significantly on LPS-induced iNOS (but not COX-2) protein in RAW 264.7 cells which was inhibited by these three compounds. Quercetin pentaacetate, but not quercetin and rutin, showed the strong inhibitory activity on PGE2 production and COX-2 protein expression in NLA/LPS or L-NAME/LPS co-treated RAW 264.7 cells. These results indicated that combinatorial treatment of L-arginine analogs and flavonoid derivates, such as quercetin pentaacetate, effectively inhibited LPS-induced NO and PGE2 productions, at the same time, inhibited enhanced expressions of iNOS and COX-2 genes.
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Su TM, Lin YC, Lu CH, Chang WN, Liliang PP, Rau CS, Liang CL, Tsai YD, Lee TJ, Chen HJ. Streptococcal brain abscess: analysis of clinical features in 20 patients. SURGICAL NEUROLOGY 2001; 56:189-94. [PMID: 11597651 DOI: 10.1016/s0090-3019(01)00551-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
BACKGROUND To assess the clinical features and therapeutic outcomes of brain abscess caused by streptococci. METHODS Twenty patients, 18 males and 2 females, aged 3 to 76 years, collected over a 14-year period, have been identified at Kaohsiung Chang Gung Memorial Hospital. RESULTS Among these 20 patients, 13 had viridans streptococci infection alone, one had non-A, non-B, and non-D streptococci infection alone, and the other 6 had mixed infections each including streptococci. The locations of all of the abscesses were supratentorial. Among these patients, 18 had a single abscess and 2 had multiple abscesses. Underlying conditions were common in our patients, including head trauma, heart disease, otopharyngeal infection, and medical procedures. Nineteen patients were treated surgically and 1 was treated with antibiotics alone. Nineteen survived and 1 died, with an overall mortality rate of 5%. CONCLUSION The clinical presentations and underlying conditions varied according to the different streptococcal species. Streptococcal brain abscesses accounted for 17% of our cases with brain abscesses, and 30% of our streptococcal infections had polymicrobial infections. Although streptococcal brain abscesses were commonly associated with otopharyngeal infections or infectious endocarditis, they also appeared to be often related to neurosurgical events or medical procedures in recent years. Based on our study, prognosis is favorable with early diagnosis and prompt treatment.
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Ban DJ, Lee TJ. Sleep duration, subjective sleep disturbances and associated factors among university students in Korea. J Korean Med Sci 2001; 16:475-80. [PMID: 11511794 PMCID: PMC3054766 DOI: 10.3346/jkms.2001.16.4.475] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Objective of this study was to look into sleep patterns of university students in association with their lifestyle, specifically to examine mean sleep duration, prevalence of sleep disturbances and their correlates. This study also aimed to examine a possible association of sleep patterns of young adults with new media like computers and videos, which were supposed to have a great influence on their lifestyle. Self-reported sleep data were derived from questionnaires administered to a total of 1,414 students of one university located in Chullabuk-do, Korea. Statistical methods such as t-test, analyses of variance, chi-square test and multivariate logistic regression were used for analysis. The mean sleep duration of the respondents was 6.7+/-1.3 hr. Of the respondents, 30.2% reported having insufficient sleep. About one third of them pointed to visual media including computers as the primary reason. The proportion of those having some types of sleep disturbances was 36.2%. The risk of subjective sleep disturbances was significantly lower among those perceiving themselves healthy than among those perceiving themselves unhealthy (OR=0.44; 95% CI: 0.34-0.57).
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Si ML, Lee TJ. Presynaptic alpha7-nicotinic acetylcholine receptors mediate nicotine-induced nitric oxidergic neurogenic vasodilation in porcine basilar arteries. J Pharmacol Exp Ther 2001; 298:122-8. [PMID: 11408533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023] Open
Abstract
We previously reported that nicotine-induced nitric oxide (NO)-mediated neurogenic vasodilation in the porcine basilar artery was dependent on intact sympathetic innervation. We further demonstrated in this artery that nicotine acted on nicotinic acetylcholine receptors (nAChRs) on presynaptic sympathetic nerve terminals to release norepinephrine (NE), which then acted on beta2-adrenoceptors located on the neighboring NOergic nerve terminals to release NO, resulting in vasodilation. The nature of the nAChRs has not been determined. The nAChR subtype mediating nicotine-induced dilation in isolated porcine basilar arterial rings denuded of endothelium was therefore examined pharmacologically and immunohistochemically. Results from using an in vitro tissue bath technique indicated that relaxation induced by nicotine (100 microM) was blocked by preferential alpha7-nAChR antagonists (methyllycaconitine and alpha-bungarotoxin) and nonspecific nAChR antagonist (mecamylamine) in a concentration-dependent manner, but was not affected by dihydro-beta-erythroidine (a preferential alpha4-nAChR antagonist). These nAChR antagonists did not affect relaxation elicited by transmural nerve stimulation (8 Hz) or that by sodium nitroprusside and NE. Results from double-labeling immunohistochemical studies in whole-mount porcine basilar and middle cerebral arteries and in cultured porcine superior cervical ganglia (SCG) indicated that alpha7-nAChR- and tyrosine hydroxylase immunoreactivities were colocalized in same nerve fibers. These results suggest the presence of functional alpha7-nAChRs on postganglionic sympathetic adrenergic nerve terminals of SCG origin, which mediate nicotine-induced neurogenic NOergic vasodilation. These findings are consistent with our hypothesis that nicotine acts on nAChRs on presynaptic sympathetic nerve terminals to release NE, which then acts on presynaptic beta2-adrenoceptors located on the neighboring NOergic nerve terminals, resulting in release of NO and dilation of porcine basilar arteries.
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Chang SE, Choi JH, Sung KJ, Moon KC, Koh JK, Lee TJ, Ro JY, Silverman JS. A case of cutaneous low-grade myofibroblastic sarcoma. J Dermatol 2001; 28:383-7. [PMID: 11510507 DOI: 10.1111/j.1346-8138.2001.tb00154.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
A 28-year-old woman presented with a recurrent nodule on the lower margin of her left nostril after laser surgery. Histologically, the nodule had an indistinct margin and was composed of interlacing fascicles of plump, spindled or stellate tumor cells with mild cytologic atypia. The tumor cells were revealed to be myofibroblasts by positivity to smooth muscle actin and negativity to desmin. A diagnosis of low grade myofibroblastic sarcoma (LGMS) was made.
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48
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Chen YC, Shen SC, Chen LG, Lee TJ, Yang LL. Wogonin, baicalin, and baicalein inhibition of inducible nitric oxide synthase and cyclooxygenase-2 gene expressions induced by nitric oxide synthase inhibitors and lipopolysaccharide. Biochem Pharmacol 2001; 61:1417-27. [PMID: 11331078 DOI: 10.1016/s0006-2952(01)00594-9] [Citation(s) in RCA: 219] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We previously reported that oroxylin A, a polyphenolic compound, was a potent inhibitor of lipopolysaccharide (LPS)-induced expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). In the present study, three oroxylin A structurally related polyphenols isolated from the Chinese herb Huang Qui, namely baicalin, baicalein, and wogonin, were examined for their effects on LPS-induced nitric oxide (NO) production and iNOS and COX-2 gene expressions in RAW 264.7 macrophages. The results indicated that these three polyphenolic compounds inhibited LPS-induced NO production in a concentration-dependent manner without a notable cytotoxic effect on these cells. The decrease in NO production was in parallel with the inhibition by these polyphenolic compounds of LPS-induced iNOS gene expression. However, these three compounds did not directly affect iNOS enzyme activity. In addition, wogonin, but not baicalin or baicalein, inhibited LPS-induced prostaglandin E2 (PGE2) production and COX-2 gene expression without affecting COX-2 enzyme activity. Furthermore, N-nitro-L-arginine (NLA) and N-nitro-L-arginine methyl ester (L-NAME) pretreatment enhanced LPS-induced iNOS (but not COX-2) protein expression, which was inhibited by these three polyphenolic compounds. Wogonin, but not baicalin or baicalein, similarly inhibited PGE2 production and COX-2 protein expression in NLA/LPS or L-NAME/LPS-co-treated RAW 264.7 cells. These results indicated that co-treatment with NOS inhibitors and polyphenolic compounds such as wogonin effectively blocks acute production of NO and, at the same time, inhibits expression of iNOS and COX-2 genes.
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Cheung K, Lee TJ. Craniopharyngioma involving supfrasellar region and sphenoid sinus: case report. CHANG GUNG MEDICAL JOURNAL 2001; 24:383-7. [PMID: 11512370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Craniopharyngiomas are benign, epithelial, slow-growing neoplasms that generally develop either in the suprasellar region or in both the suprasellar and intrasellar regions. They rarely occurs in the infrasellar region. Based on embryologic development of adenohypophysis, the tumor can arise along the path of the craniopharyngeal duct. We report on an 8- year-old boy who presented to us with headache and anorexia for several weeks during May 1999. Brain MRI revealed a huge sphenoid tumor. The tumor was completely excised by functional endoscopic sinus surgery on 12th August 1999. The postoperative course was smooth and no evidence of tumor recurrence was found on his latest follow-up visit in February, 2000. From the clinical experience with this case, functional endoscopic sinus surgery is an alternative and a less-harmful surgical procedure for this kind of benign sphenoid tumor. Moreover, embryology development, epidemiology, clinical presentation, diagnostic method and treatment of craniopharyngioma are discussed.
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Roberts HC, Roberts TP, Smith WS, Lee TJ, Fischbein NJ, Dillon WP. Multisection dynamic CT perfusion for acute cerebral ischemia: the "toggling-table" technique. AJNR Am J Neuroradiol 2001; 22:1077-80. [PMID: 11415901 PMCID: PMC7974776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
A new CT perfusion technique providing extended anatomic coverage was evaluated in 12 patients with suspected acute middle cerebral artery ischemia. With a multidetector CT scanner, scans were obtained in an alternating fashion at two distinct "toggling" table positions (two 1-cm sections each) during a 40-mL contrast agent bolus (approximately 5 seconds per image), and perfusion parameter maps were created. The CT perfusion results were compared with follow-up images. Nine patients showed focal perfusion abnormalities in at least one section, most commonly on mean transit time maps. Using a single table location would have underestimated or missed the involved tissue in most cases. In three of 12 patients, perfusion maps failed to delineate any abnormality. In two patients, perfusion and diffusion MR imaging confirmed the absence of perfusion abnormality and tissue injury, respectively. In one case, a small ischemic injury was revealed by diffusion MR imaging. By using the toggling-table approach, perfusion images can be obtained over an extended anatomic area and, thus, reveal the presence and the extent of presumed tissue injury.
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