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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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78
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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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82
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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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84
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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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85
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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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86
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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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Edvinsson L, Elsås T, Suzuki N, Shimizu T, Lee TJ. Origin and Co-localization of nitric oxide synthase, CGRP, PACAP, and VIP in the cerebral circulation of the rat. Microsc Res Tech 2001; 53:221-8. [PMID: 11301497 DOI: 10.1002/jemt.1086] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The origin of perivascular nerve fibres storing nitric oxide synthase (NOS) and co-localisation with perivascular neuropeptides were examined in the rat middle cerebral artery (MCA) by retrograde tracing with True Blue (TB) in combination with immunocytochemistry. Application of TB to the proximal part of the middle cerebral artery labelled nerve cell bodies ipsilaterally in the trigeminal, sphenopalatine, otic, and superior cervical ganglia. A few labelled cell bodies were seen contralaterally, suggesting bilateral innervation. In the parasympathetic sphenopalatine and otic ganglia, numerous TB-labelled cell bodies contained neuronal NOS (C- and N-terminal), vasoactive intestinal peptide (VIP), and pituitary adenylate cyclase activating peptide (PACAP). In the trigeminal ganglion, almost all TB-labelled cell bodies contained calcitonin gene-related peptide (CGRP) but only a few cells contained NOS. In the superior cervical ganglion, the majority of the TB-labelled nerve cells contained neuropeptide Y (NPY) but none of them contained NOS. Removal of the ipsilateral sphenopalatine ganglion caused a slight reduction in the number of perivascular VIP-, PACAP-, and NOS-containing fibres after 3 days in the MCA while there was no difference at 2 and 4 weeks after the denervation as compared to control. This indicates that the parasympathetic VIP-, PACAP-, and NOS-immunoreactive nerve fibres in the rat MCA originate from several sources.
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90
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Lee TJ, Liu J, Evans MS. Cholinergic-nitrergic transmitter mechanisms in the cerebral circulation. Microsc Res Tech 2001; 53:119-28. [PMID: 11301487 DOI: 10.1002/jemt.1076] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Cerebral blood vessels from several species are innervated by vasodilator nerves. Acetylcholine (ACh) released from parasympathetic cholinergic nerves was first suggested to be the transmitter for vasodilation. Results from pharmacological studies in isolated cerebral arterial ring preparations, however, have demonstrated that nitric oxide (NO) but not ACh mediates the major component of neurogenic vasodilation. More recently, ACh and NO have been shown to co-release from the same cholinergic-nitrergic nerves, and that ACh acts as a presynaptic transmitter in modulating NO release. In this communication, evidence for the neuronal origin of NO and possible role of ACh in modulating NO release in large cerebral arteries at the base of the brain will be discussed.
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91
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Lee TJ, Nakano K, Matsumara M. Ultrasonic irradiation for blue-green algae bloom control. ENVIRONMENTAL TECHNOLOGY 2001; 22:383-390. [PMID: 11329801 DOI: 10.1080/09593332208618270] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A novel application of ultrasonic irradiation for rapid control of blue-green algae (BGA) bloom was investigated. Potassium iodide (KI) experiments demonstrated that frequency and input power are the major factors that affect the ultrasonic irradiation intensity. Short exposure (3 s) to ultrasonic irradiation (120 W input power, 28 kHz) effectively settled naturally growing BGA suspension. Electron microscopy reconfirmed that sedimentation was caused by the disruption and collapse of gas vacuoles after ultrasonic exposure. Moreover, even after 5 min of exposure to ultrasonic irradiation (1200 W input power, 28 kHz) the microcystin concentration in BGA suspensions did not increase. For the same input power (120 W), a lower frequency (28 kHz) was found to be more effective in decreasing the photosynthetic activity of BGA than a higher frequency (100 kHz). The sonicated cells did not proliferate when they were cultured in conditions that simulated the bottom of water bodies (i.e. with limited light (400 lx) or no light and non-aerated or aerated (1 l min-1)). Furthermore, ultrasonic irradiation did not only collapse gas vacuoles and precipitate BGA, but may have also inflicted damage on the photosynthetic system of the BGA.
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Weisman JL, Lee TJ, Head-Gordon M. Electronic spectra and ionization potentials of a stable class of closed shell polycyclic aromatic hydrocarbon cations. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2001; 57:931-945. [PMID: 11345264 DOI: 10.1016/s1386-1425(00)00454-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Due to their stability, closed shell polycyclic aromatic hydrocarbon (PAH) cations are possible candidates as carriers for some of the diffuse interstellar bands (DIBs). The electronic absorption spectra and ionization potentials of several closed shell PAH cations are determined in this study. We use density functional theory (DFT) at the BLYP/6-31G* level to determine the ionization potentials and thus confirm the stability of the PAH cations of interest. We use time-dependent density functional theory (TDDFT), again at the BLYP/6-31G* level, to calculate the vertical excitation energies and oscillator strengths of the PAH cations. We observe dominant single absorptions within the DIB spectral region of interest in all of the PAH cation spectra except for the smallest member of the series.
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Kim HJ, Lee TJ, Kim MK, Choi YH, Myung SC, Kim YS, Song KY. Muellerianosis of the urinary bladder, endocervicosis type: a case report. J Korean Med Sci 2001; 16:123-6. [PMID: 11289391 PMCID: PMC3054573 DOI: 10.3346/jkms.2001.16.1.123] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [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
This case reports muellerianosis of the urinary bladder, showing glandular lesions made up of endocervical type glands, in a 36-yr-old woman. The patient presented with lower abdominal discomfort and pain on voiding. The patient had undergone two Cesarean sections 5 yr and 3 yr earlier. On a pelvic ultrasonography, a well-circumscribed mass, 2.2x0.8 cm in dimension, was found with luminal polypoid projection in the posterior wall of the urinary bladder. The patient had a transurethral resection of the bladder mass. Histologically, the tumor was composed of irregularly shaped glands lined by endocervical mucous epithelium in the muscularis propria of the urinary bladder. Some glands exhibited cystic dilatation and contained mucinous secretions. The glands elicited no desmoplastic tissue reaction. The intraluminal mucin often contained polymorphonuclear leukocytes. The glands were mostly lined by tall columnar and bland looking mucous cells with mucin secretion. The ciliated cells were rarely observed. No endometrial component is noted. It would be appropriate to designate this lesion as "Muellerianosis of the urinary bladder, endocervicosis type". Awareness of the lesion and attention to its typical histologic features should facilitate its crucial distinction from adenocarcinoma.
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Kwak BK, Shim HJ, Park US, Lee TJ, Paeng SS, Lee CJ, Lim HK, Park CK. Correlation of VEGF with contrast enhancement on dual-phase dynamic helical CT in liver tumors: preliminary study. J Korean Med Sci 2001; 16:83-7. [PMID: 11289406 PMCID: PMC3054564 DOI: 10.3346/jkms.2001.16.1.83] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [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
The purpose of this preliminary study is to elucidate that vascular endothelial growth factor (VEGF) influences contrast enhancement of hepatic tumors on computed tomography (CT). Fourteen patients with hepatic tumors (11 hepatocellular carcinomas; 3 metastatic cancers) underwent a dual-phase dynamic helical CT or computed tomographic hepatic arteriography. The attenuation of each mass was determined as hyperattenuation, isoattenuation or hypoattenuation with respect to the adjacent nontumorous parenchyma. Gun-needle biopsy was done for each tumor, and paraffin sections were immunostained with anti- VEGF antibody by the avidin-biotin-peroxidase complex method. The pathologic grade was made by intensity (1 +, 2+, 3+) and area (+/-, 1 +, 2+). The tumor ranged 2.0-14.0 cm in size (mean, 5.8 cm). In arterial phase, the intensity was not correlated with the degree of enhancement (p=0.086). However, the correlation between the attenuation value of hepatic arterial phase and the area of positive tumor cells was statistically significant (p=0.002). VEGF may be the factor that enhances the hepatic mass with water-soluble iodinated contrast agent in CT.
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Badawy SI, Lee TJ, Menning MM. Effect of drug substance particle size on the characteristics of granulation manufactured in a high-shear mixer. AAPS PharmSciTech 2000; 1:E33. [PMID: 14727898 PMCID: PMC2750457 DOI: 10.1208/pt010433] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
DPC 963 is a non-nucleoside reverse transcriptase inhibitor with low aqueous solubility. The effect of DPC 963 drug substance particle size on the characteristics of granules manufactured by high-shear wet granulation was evaluated. The wet granulation process was used to manufacture a DPC 963 formulation with high drug loading. The formulation was manufactured using drug substance lots with different particle size distributions. Granulation particle size distribution, porosity, and compressibility were determined. A uniaxial compression test was also performed on moist compacts of the formulation prepared with different particle size distributions. Particle agglomeration behavior was affected by drug substance particle size. Granulation geometric mean diameter and fraction with particle size greater than 250 microm was inversely proportional to the drug substance particle size. Mercury intrusion porosimetry revealed higher pore volumes for the granules manufactured using the drug substance with the smaller particle size, suggesting lower tendency for granule densification than for that manufactured with the larger drug substance particle size. Granulation compressibility was also sensitive to changes in drug substance particle size. A decreased drug substance particle size led to increased granulation compressibility. Results from the uniaxial compression experiments suggested that the effect of particle size on granulation growth is the result of increased densification propensity, which in turn results from increased drug substance particle size.
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Lee TJ, Bae JJ, Lee JS, Lee SY, Kim HJ, Kim SK, Lee JY, Lee TY. Abrogation of the p16-Rb pathway in Korean hepatocellular carcinomas. HEPATO-GASTROENTEROLOGY 2000; 47:1663-8. [PMID: 11149028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
BACKGROUND/AIMS The tumor suppressor gene p16 on human chromosome 9p21 encodes a specific inhibitor of the cyclin D-CDK4 complex which inactivates the Rb protein by hyperphosphorylation. Many reports show that p16 is inactivated in a variety of human cancers. We investigated whether abnormalities involving p16 and Rb are associated with hepatocellular carcinomas in Korea. METHODOLOGY We performed loss of heterozygosity analysis on 9 primary hepatocellular carcinomas using 7 microsatellite markers spanning human chromosome 9p. Reverse transcriptase-PCR, ribonuclease protection assay, and immunoblotting were used to examine the expression of p16 and Rb in 8 hepatocellular carcinoma cell lines, including 5 from Korean patients. Exons 1 and 2 of the p16 gene were sequenced. RESULTS We found a 33% loss of heterozygosity at the D9S171 locus (9p21 region) in the primary hepatocellular carcinomas. The p16 protein was not found in 4 out of 5 (80%) of the Korean cell lines. Among them, 2 cell lines lacked p16 protein and had the following point mutations in p16 exon 2: Asp125 to Asn and Arg58 to Ter. Two of the Korean cell lines and the SK-Hep-1 cells contained deletions in the p16 gene. All cell lines examined, except Hep 3B, expressed Rb protein, which in all cases was dominantly hyperphosphorylated (inactivated). CONCLUSIONS Our results suggest that p16 and Rb abnormalities are associated with hepatocellular carcinomas in the Korean population.
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97
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Lee TJ, Kim SJ, Park JH. Influence of the sequence variations of the HLA-DR promoters derived from human melanoma cell lines on nuclear protein binding and promoter activity. Yonsei Med J 2000; 41:593-9. [PMID: 11079619 DOI: 10.3349/ymj.2000.41.5.593] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
In previous studies we reported that the expression of HLA-DR on melanoma cell lines was differentially modulated by IFN- gamma and that the transcription rate was responsible for this differential modulation. We have also reported the nucleotide sequence variations in the promoter region of HLA-DR genes, and proposed that differences in the promoter activity by the sequence variations of the HLA-DR promoters might contribute to such a differential transcriptional regulation at the promoter level. In this study, in order to assess whether the sequence variations of the HLA-DR promoters affect the factor binding and exert influence on the promoter activity, nuclear factor binding to our previous six HLA-DRA and fourteen HLA-DRB promoter clones was evaluated with the nuclear protein extracted from a B-lymphoblastoid cell line (BLCL), BH, together with the chloramphenicol acetyltransferase (CAT) reporter assay. In the HLA-DRA promoters, clone #35 containing one bp nucleotide sequence variation at the octamer binding site (OCT) (GATTTGC to GATCTGC) showed relatively weak factor binding. In the HLA-DRB promoters, clusters I, III, and IV of our previous HLA-DRB promoter homologues, containing one bp nucleotide sequence variation (GATTCG) in their Y boxes exhibited weak factor binding and CAT activity compared to other clusters (GATTGG) that showed strong factor binding and CAT activity. This data suggests chat the binding patterns of transcription factors influenced by the nucleotide sequence variations of the HLA-DR promoter could affect the promoter activity and the DNA sequence elements in the HLA-DR promoter could mediate transcriptional regulation.
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98
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Philip AT, Amin MB, Tamboli P, Lee TJ, Hill CE, Ro JY. Intravesical adipose tissue: a quantitative study of its presence and location with implications for therapy and prognosis. Am J Surg Pathol 2000; 24:1286-90. [PMID: 10976704 DOI: 10.1097/00000478-200009000-00013] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Accurate pathologic staging of carcinomas of the urinary bladder involves assessment of invasion by the tumor into the bladder wall and beyond into perivesical soft tissue. The presence of tumor within perivesical soft tissue implies pathologic stage pT3 (AJCC/UICC system, 1997). In traditional textbooks of histology, anatomy, pathology, and in the literature, other than a single case report and a brief reference in another paper, there is no information on the presence of adipose tissue in the lamina propria or muscularis propria of the urinary bladder. Nine hundred forty-three sections from 139 cystectomy specimens were evaluated for the presence, location, and quantity of adipose tissue within the lamina propria and muscularis propria. The histology of the perivesical soft tissues and the nature of its delineation from muscularis propria were also analyzed. Adipose tissue was seen within the lamina propria in 53% (74 of 139) of cystectomies and in 17.6% (166 of 943) of the examined sections. It was located predominantly in the deep lamina propria (at or below the muscularis mucosae) in 81.1% (60 of 74) of the cystectomies and in 91% (151 of 166) of the sections. Within the lamina propria it was predominantly seen as small localized aggregates in 92% (153 of 166) of sections. All cases showed adipose tissue within the muscularis propria. Adipose tissue was identified within the superficial (inner) muscularis propria in 54% (512 of 943) of sections and was predominantly in small aggregates in 80.5% (412 of 512) of sections. It was in moderate to abundant quantities within the deep (outer) muscularis propria in 60.7% (572 of 943) of sections. The perivesical soft tissue was almost exclusively composed of adipose tissue with variable vascularity. Delineation of the perivesical adipose tissue from the deep (outer) muscularis propria was typically indistinct because muscle bundles of the latter haphazardly merged with the perivesical adipose tissue. Based on these findings, we conclude that adipose tissue is frequently present in the lamina propria and muscularis propria of the urinary bladder wall, and is usually scant in the former location and frequently abundant in the latter. Awareness of the high frequency of adipose tissue within the urinary bladder wall has prognostic and therapeutic implications. In transurethral resection of bladder tumor (TURBT) specimens, misinterpretation of tumor infiltrating adipose tissue within lamina propria (pT1) as perivesical soft tissue involvement (pT3) may potentially result in unwarranted aggressive management. Substaging of muscle invasive tumors should be performed in cystectomy specimens only, because the junction of muscularis propria and the perivesical adipose tissue is typically ill-defined. Muscularis propria adipose tissue in TURBT specimens may be erroneously assumed to be perivesical adipose tissue, potentially leading to overstaging of the primary tumor.
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99
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Lee TJ, Zhang W, Sarwinski S. Presynaptic beta(2)-adrenoceptors mediate nicotine-induced NOergic neurogenic dilation in porcine basilar arteries. Am J Physiol Heart Circ Physiol 2000; 279:H808-16. [PMID: 10924081 DOI: 10.1152/ajpheart.2000.279.2.h808] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We previously reported that nicotine-induced nitric oxide (NO)-mediated cerebral neurogenic vasodilation was dependent on intact sympathetic innervation. We hypothesized that nicotine acted on sympathetic nerve terminals to release norepinephrine (NE), which then acted on adrenoceptors located on the neighboring nitric oxidergic (NOergic) nerve terminals to release NO, resulting in vasodilation. The adrenoceptor subtype in mediating nicotine-induced vasodilation 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 propranolol and preferential beta(2)-adrenoceptor antagonists (ICI-118,551 and butoxamine), in a concentration-dependent manner, blocked the relaxation induced by nicotine (100 microM) without affecting the relaxation elicited by transmural nerve stimulation (TNS, 8 Hz). In contrast, preferential beta(1)-adrenoceptor antagonists (atenolol and CGP-20712A) did not affect either nicotine- or TNS-induced relaxation. Results of double-labeling studies indicated that beta(2)-adrenoceptor immunoreactivities and NADPH diaphorase reactivities were colocalized in the same nerve fibers in basilar and middle cerebral arteries. These findings suggest that NE, which is released from sympathetic nerves upon application of nicotine, acts on presynaptic beta(2)-adrenoceptors located on the NOergic nerve terminals to release NO, resulting in vasodilation. In addition, nicotine-induced relaxation was enhanced by yohimbine, an alpha(2)-adrenoceptor antagonist, which, however, did not affect the relaxation elicited by TNS. Prazosin, an alpha(1)-adrenoceptor antagonist, on the other hand, did not have any effect on relaxation induced by either nicotine or TNS. The predominant facilitatory effect of beta(2)-adrenoceptors in releasing NO may be compromised by presynaptic alpha(2)-adrenoceptors.
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MESH Headings
- Adrenergic beta-Antagonists/pharmacology
- Animals
- Basilar Artery/drug effects
- Basilar Artery/innervation
- Basilar Artery/physiology
- Butoxamine/pharmacology
- Endothelium, Vascular/physiology
- Female
- In Vitro Techniques
- Male
- Models, Cardiovascular
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/innervation
- Muscle, Smooth, Vascular/physiology
- Nicotine/pharmacology
- Nitric Oxide/physiology
- Prazosin/pharmacology
- Propanolamines/pharmacology
- Receptors, Adrenergic, beta-2/drug effects
- Receptors, Adrenergic, beta-2/physiology
- Swine
- Vasodilation/drug effects
- Vasodilation/physiology
- Yohimbine/pharmacology
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Chen Y, Yang L, Lee TJ. Oroxylin A inhibition of lipopolysaccharide-induced iNOS and COX-2 gene expression via suppression of nuclear factor-kappaB activation. Biochem Pharmacol 2000; 59:1445-57. [PMID: 10751555 DOI: 10.1016/s0006-2952(00)00255-0] [Citation(s) in RCA: 253] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Polyphenols are major components of many traditional herbal remedies, which exhibit several beneficial effects including anti-inflammation. The exact mechanism of the anti-inflammatory action of polyphenols, however, has not been determined. In the present study, we examined the effects of eight different polyphenols isolated from Chinese herbs, including two flavonoids (myricitrin and oroxylin A), four ellagitannins (penta-O-galloyl-beta-glucopyranose, woodfordin C, oenothein B, and cuphiin D1), and two anthraquinones (emodin and physcion), on lipopolysaccharide (LPS)-induced nitric oxide (NO) production, and inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) gene expression in RAW264.7 macrophages. The results indicated that only oroxylin A and emodin concentration-dependently inhibited LPS-induced NO production. The remaining compounds slightly inhibited LPS-induced NO production only at the highest concentration examined. Furthermore, oroxylin A inhibited the expression of LPS-induced iNOS and COX-2 proteins and mRNAs without an appreciable cytotoxic effect on RAW264.7 cells. Emodin also inhibited LPS-induced iNOS protein as potently as oroxylin A, but it inhibited LPS-induced iNOS mRNA expression only slightly and did not affect COX-2 mRNA and proteins. This was consistent with the findings that oroxylin A but not emodin or physcion inhibited prostaglandin E(2) synthesis induced by LPS. The inhibitory effects of oroxylin A on LPS-induced iNOS and COX-2 gene expression were also demonstrated in Bcl-2-overexpressing RAW264.7 macrophages, suggesting that oroxylin A inhibition of iNOS and COX-2 expression was not due to its antioxidant effect. Furthermore, oroxylin A but not emodin blocked nuclear factor-kappaB (NF-kappaB) binding and transcriptional activation associated with decreased p65 proteins in the nucleus induced by LPS. These results indicated that oroxylin A, an active component in Huang Qin, inhibited LPS-induced iNOS and COX-2 gene expression by blocking NF-kappaB activation, whereas emodin inhibition of LPS-induced iNOS expression may be mediated by a different transcription factor.
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