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Park SH, Xiang R, Lee KW. Brownian Coagulation of Fractal Agglomerates: Analytical Solution Using the Log-Normal Size Distribution Assumption. J Colloid Interface Sci 2000; 231:129-135. [PMID: 11082256 DOI: 10.1006/jcis.2000.7102] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
An analytical solution to Brownian coagulation of fractal agglomerates in the continuum regime that provides time evolution of the particle size distribution is presented. The theoretical analysis is based on representation of the size distribution of coagulating agglomerates with a time-dependent log-normal size distribution function and employs the method of moments together with suitable simplifications. The results are found in the form that extends the spherical particle solution previously obtained by K. W. Lee (J. Colloid Interface Sci. 92, 315-325 (1983)). The results show that the mass fractal dimension has a significant effect on the size distribution evolution during coagulation. When the obtained solution was compared with numerical results, good agreement was found. The self-preserving size distribution of nonspherical agglomerates is discussed. Copyright 2000 Academic Press.
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Han JW, Ahn SH, Park SH, Wang SY, Bae GU, Seo DW, Kwon HK, Hong S, Lee HY, Lee YW, Lee HW. Apicidin, a histone deacetylase inhibitor, inhibits proliferation of tumor cells via induction of p21WAF1/Cip1 and gelsolin. Cancer Res 2000; 60:6068-74. [PMID: 11085529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Apicidin [cyclo(N-O-methyl-L-tryptophanyl-L-isoleucinyl-D-pipecolinyl -L-2-amino-8-oxodecanoyl)] is a fungal metabolite shown to exhibit antiparasitic activity by the inhibition of histone deacetylase (HDAC). In this study, we evaluated apicidin as a potential antiproliferative agent. Apicidin showed a broad spectrum of antiproliferative activity against various cancer cell lines, although with differential sensitivity. The antiproliferative activity of apicidin on HeLa cells was accompanied by morphological changes, cell cycle arrest at G1 phase, and accumulation of hyperacetylated histone H4 in vivo as well as inhibition of partially purified HDAC in vitro. In addition, apicidin induced selective changes in the expression of p21WAF1/Cip1 and gelsolin, which control the cell cycle and cell morphology, respectively. Consistent with increased induction of p21WAF1/Cip1, phosphorylation of Rb protein was markedly decreased, indicating the inhibition of cyclin-dependent kinases, which became bound to p21WAF1/Cip1. The effects of apicidin on cell morphology, expression of gelsolin, and HDAC1 activity in vivo and in vitro appeared to be irreversible, because withdrawal of apicidin did not reverse those effects, whereas the induction of p21WAF1/Cip1 by apicidin was reversible. Taken together, the results suggest that induction of histone hyperacetylation by apicidin is responsible for the antiproliferative activity through selective induction of genes that play important roles in the cell cycle and cell morphology.
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428
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Park SH, Araki S, Nakata A, Kim YH, Park JA, Tanigawa T, Yokoyama K, Sato H. Effects of occupational metallic mercury vapour exposure on suppressor-inducer (CD4+CD45RA+) T lymphocytes and CD57+CD16+ natural killer cells. Int Arch Occup Environ Health 2000; 73:537-42. [PMID: 11100948 DOI: 10.1007/s004200000173] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
OBJECTIVES To examine the effects of metallic mercury vapour on the cellular and humoral immune system. METHODS We measured T lymphocyte and natural killer (NK) cell subpopulations, B lymphocytes, and serum immunoglobulins (i.e. IgG, IgA and IgM) together with total T (CD3 +) lymphocytes and total lymphocytes in blood samples from 20 male, fluorescent-lamp makers (mercury workers) and the same number of gender-, age- and smoking-matched controls. Urinary concentrations of inorganic mercury (UHg) in the 20 workers ranged from 1.8 to 163.5 (mean 44.8) microg/l. They had been exposed to mercury vapour for 4 to 62 (mean 31) months. RESULTS Numbers of CD4+CD45RA+ (suppressor-inducer) T lymphocytes and total CD4+ T lymphocytes in the mercury workers were significantly smaller than those in the controls (paired-sample t-test, P < 0.01). The number of CD57+CD16+ NK cells was inversely correlated with UHg. CONCLUSION It is suggested that numbers of CD4+CD45RA+ T lymphocytes and CD57+CD16+ NK cells are inversely affected by exposure to metallic mercury vapour in workers, with an average urinary inorganic mercury concentration of 45 microg/l being found.
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Lee SK, Kim JY, Hong KS, Nam HW, Park SH, Chung CK. The clinical usefulness of ictal surface EEG in neocortical epilepsy. Epilepsia 2000; 41:1450-5. [PMID: 11077459 DOI: 10.1111/j.1528-1157.2000.tb00121.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE Localizable scalp EEGs, during ictal episodes, appear to be rare in neocortical epileptic syndromes. However, studies based on large numbers of patients are also rare. This study aims to identify the characteristic patterns of variable neocortical epilepsies and to evaluate their clinical usefulness in the localization of epileptogenic focuses. METHODS We retrospectively assessed 394 noninvasive ictal recordings from 86 patients who subsequently underwent invasive study and resective surgery. Ictal EEGs were recorded using a video-EEG monitoring system with electrodes placed according to the International 10-20 system, with additional anterior temporal electrodes. The ictal recordings were analyzed according to localizing accuracy and frequency characteristics. The durations of discrete or regional ictal rhythms were also measured. RESULTS The percentage of discrete or regional EEGs was 23% in frontal lobe epilepsy, 52% in lateral temporal lobe epilepsy, 70% in occipital lobe epilepsy, and 10% in parietal lobe epilepsy. In order of frequency, the localizable ictal rhythms were theta, beta, alpha, delta, and rhythmic spike-and-wave. The duration of discrete or regional ictal rhythms was significantly shorter in frontal lobe epilepsy and parietal lobe epilepsy than in other epilepsies. Ictal beta activity was the most common rhythm in discrete-patterned EEGs. Structural lesions found on MRI did not significantly affect the localization of epileptogenic focuses in the patients. The type of seizure was not related to the degree of localization, with the exception of simple partial seizure. CONCLUSIONS Ictal surface EEG was clinically helpful in the localization of epileptogenic focuses in at least some neocortical epileptic syndromes.
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Park SH, Ryu SH, Suh PG, Kim H. Assignment1 of human PLCB2 encoding PLC beta2 to human chromosome 15q15 by fluorescence in situ hybridization. CYTOGENETICS AND CELL GENETICS 2000; 83:48-9. [PMID: 9925923 DOI: 10.1159/000015166] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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431
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Park SH, Ryu SH, Suh PG, Kim H. Assignment of human PLD2 to chromosome band 17p13.1 by fluorescence in situ hybridization. CYTOGENETICS AND CELL GENETICS 2000; 82:225. [PMID: 9858823 DOI: 10.1159/000015106] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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432
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Park SH, Lee SG, Kim Y, Song K. Assignment of a human putative RNA helicase gene, DDX3, to human X chromosome bands p11.3-->p11.23. CYTOGENETICS AND CELL GENETICS 2000; 81:178-9. [PMID: 9730595 DOI: 10.1159/000015022] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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433
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Park SH, Chun YH, Ryu SH, Suh PG, Kim H. Assignment of human PLD1 to human chromosome band 3q26 by fluorescence in situ hybridization. CYTOGENETICS AND CELL GENETICS 2000; 82:224. [PMID: 9858822 DOI: 10.1159/000015105] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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434
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Hur DY, Kim S, Kim YI, Min HY, Kim DJ, Lee DS, Cho D, Hwang YI, Hwang DH, Park SH, Ahn HK, Chang KY, Kim YB, Lee WJ. CM1, a possible novel activation molecule on human lymphocytes. Immunol Lett 2000; 74:95-102. [PMID: 10996383 DOI: 10.1016/s0165-2478(00)00201-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
CM1 (centrocyte/-blast marker 1) defined by a mAb developed against concanavalin-A activated PBMC, is expressed specifically on some tonsillar germinal center (GC) B cells. In single flow cytometric analysis, the bone marrow did not express these molecules nor did the PBMC or the thymocytes. The peripheral B lymphocytes showed more than 90% positive, while the peripheral T lymphocytes showed approximately 60% positive at 48 h after activation by PMA/ionomycin, respectively. A western blot analysis and an immunoprecipitation for CM1 showed a band at 70 kDa. Cross-linking of CM1 with anti-CM1 mAb induced apoptosis of the GC B cells (CD38(+)IgD(-)). Immunohistochemical staining revealed that the CM1 molecule is distributed over the entire area except the proximal dark zone of the tonsillar germinal centers. These results suggest that the CM1 molecule might be involved in differentiation of the germinal center B cells as one of the novel centrocyte markers.
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435
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Park SH, Cho HN, Lee SJ, Kim TH, Lee Y, Park YM, Lee YJ, Cho CK, Yoo SY, Lee YS. Hsp25-induced radioresistance is associated with reduction of death by apoptosis: involvement of Bcl2 and the cell cycle. Radiat Res 2000; 154:421-8. [PMID: 11023606 DOI: 10.1667/0033-7587(2000)154[0421:hiriaw]2.0.co;2] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
We previously demonstrated the protective effect of the small heat-shock protein against oxidative damage induced by tumor necrosis factor alpha. Here we have extended our studies of the possible role of Hsp25 in ionizing radiation-induced damage. For these studies, we transfected murine fibroblast L929 cells with the Hsp25 gene and selected three stably transfected clones. Hsp25 overexpression conferred radioresistance as detected by clonogenic survival and induction of apoptosis. Interestingly, the Hsp25-transfected cells showed an increase in the level of the anti-apoptosis molecule Bcl2. We also observed alterations of cell growth in the Hsp25-transfected cells. The cell cycle time of Hsp25-transfected cells was 3-4 h slower than that of vector-transfected control cells. Flow cytometry analysis of synchronized cells at late G(1) phase by mimosine treatment also showed the growth delay in Hsp25-overexpressing cells. In addition, reduced cyclin D1, cyclin A and Cdc2 levels and increased levels of Cdkn1a (also known as p21(Waf)) were observed in Hsp25-transfected cells, which probably caused the reduction in cell growth. In addition, synchronization by mimosine treatment only partially altered radioresistance in the Hsp25-transfected cells. Taken together, these data suggest that Hsp25-induced radioresistance is associated with growth delay as well as induction of Bcl2.
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436
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Park SH, Jung KC, Ro JY, Kang GH, Khang SK. 5' CpG island methylation of p16 is associated with absence of p16 expression in glioblastomas. J Korean Med Sci 2000; 15:555-9. [PMID: 11068994 PMCID: PMC3054673 DOI: 10.3346/jkms.2000.15.5.555] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Recent evidence shows that transcriptional silencing as a consequence of hypermethylation of CpG islands is an important mechanism in the inactivation of p16INK4 tumor suppressor gene. This study is designed to clarify the significance of p16INK4 hypermethylation in 23 cases of glioblastomas (GBMs) by methylation-specific polymerase chain reaction (PCR) and p16 immunostaining. Fourteen cases (60.9%) out of 23 GBMs revealed hypermethylation on p16. p16 immunostaining revealed that 13 (93%) of these 14 hypermethylation cases showed complete loss of immunoreactivity and only one (7%) case retained immunoreactivity. Among 9 methylation-negative cases, 4 were immunonegative, which might be related to mutations or deletions other than hypermethylation. The most significant finding was that of 17 cases with immunonegativity, 13 cases (76.5%) showed hypermethylation. We reconfirmed that p16 hypermethylation may be one of the major mechanisms of tumorigenesis of GBMs and the results between the methylation specific-PCR study and p16 immunostaining had a good correlation.
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437
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Park SH, Chang KH, Song IC, Kim YJ, Kim SH, Han MH. Diffusion-weighted MRI in cystic or necrotic intracranial lesions. Neuroradiology 2000; 42:716-21. [PMID: 11110071 DOI: 10.1007/s002340000394] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Our purpose was to investigate the signal intensities of cystic or necrotic intracranial lesions on diffusion-weighted MRI (DWI) and measure their apparent diffusion coefficients (ADC). We examined 39 cystic or necrotic intracranial lesions in 33 consecutive patients: five malignant gliomas, seven metastases, two other necrotic tumours, a haemangioblastoma, three epidermoids, an arachnoid cyst, seven pyogenic abscesses, 12 cases of cysticercosis and one of radiation necrosis. DWI was performed on a 1.5 T unit using a single-shot echo-planar spin-echo pulse sequence with b 1,000 s/mm2. The signal intensity of the cystic or necrotic portion on DWI was classified by visual assessment as markedly low (as low as cerebrospinal fluid), slightly lower than, isointense with, and slightly or markedly higher than normal brain parenchyma. ADC were calculated in 31 lesions using a linear estimation method with measurements from b of 0 and 1,000 s/ mm2. The cystic or necrotic portions of all neoplasms (other than two metastases) gave slightly or markedly low signal, with ADC of more than 2.60 x 10(-3) mm2/s. Two metastases in two patients showed marked high signal, with ADC of 0.50 x 10(-3) mm2/s and 1.23 x 10(-3) mm2/s, respectively. Epidermoids showed slight or marked high signal, with ADC of less than 1.03 x 10(-3) mm2/s. The arachnoid cyst gave markedly low signal, with ADC of 3.00 x 10(-3) mm2/s. All abscesses showed marked high signal, with ADC below 0.95 x 10(-3) mm2/s. The cases of cysticercosis showed variable signal intensity; markedly low in five, slightly low in three and markedly high in four.
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Lim DK, Park SH, Choi WJ. Subacute nicotine exposure in cultured cerebellar cells increased the release and uptake of glutamate. Arch Pharm Res 2000; 23:488-94. [PMID: 11059829 DOI: 10.1007/bf02976578] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Cerebellar granule and glial cells prepared from 7 day-old rat pups were used to investigate the effects of sub-acute nicotine exposure on the glutamatergic nervous system. These cells were exposed to nicotine in various concentrations for 2 to 10 days in situ. Nicotine-exposure did not result in any changes in cerebellar granule and glial cell viability at concentrations of up to 500 microM. In cerebellar granule cells, the basal extracellular levels of glutamate, aspartate and glycine were enhanced in the nicotine-exposed granule cells. In addition, the responses of N-methyl-D-aspartate (NMDA)-induced glutamate release were enhanced at low NMDA concentrations in the nicotine-exposed granule cells. However, this decreased at higher NMDA concentrations. The glutaminase activity was increased after nicotine exposure. In cerebellar glial cells, glutamate uptake in the nicotine-exposed glial cells were either increased at low nicotine exposure levels or decreased at higher levels. The inhibition of glutamate uptake by L-trans-pyrollidine-2,4-dicarboxylic acid (PDC) was lower in glial cells exposed to 50 microM nicotine. Glutamine synthetase activity was lower in glial cells exposed to 100 or 500 microM of nicotine. These results indicate that the properties of cerebellar granule and glial cells may alter after subacute nicotine exposure. Furthermore, they suggest that nicotine exposure during development may modulate glutamatergic nervous activity.
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Kim H, Jung YK, Jo DG, Park SH. Assignment of the rat calcineurin inhibitor gene (Cain) to rat chromosome band 20p12 by fluorescence in situ hybridization. CYTOGENETICS AND CELL GENETICS 2000; 89:236-7. [PMID: 10965132 DOI: 10.1159/000015622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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440
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Lee BH, Park SH, Won R, Park YG, Sohn JH. Antiallodynic effects produced by stimulation of the periaqueductal gray matter in a rat model of neuropathic pain. Neurosci Lett 2000; 291:29-32. [PMID: 10962146 DOI: 10.1016/s0304-3940(00)01375-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
It has been well documented that there is opioid resistance in neuropathic pain. This indicates that the endogenous opioid system may not be involved effectively in modulating neuropathic pain. The present study sought to determine if activation of the descending pain inhibition system might produce analgesia in the animal neuropathic model we developed. Under ketamine anesthesia, male Sprague-Dawley rats were chronically implanted with stimulating electrodes in the ventral periaqueductal gray matter (PAG) and both the tibial and sural nerves of the sciatic nerve branches were severed. Pain sensitivity was measured with a von Frey filament and acetone applied to the sensitive area for 1 week postoperatively. Rats with neuropathic pain syndrome after transection of the tibial and sural nerves were tested as to the analgesic effects of ventral PAG stimulation for an additional two weeks. Electrical stimulation of the ventral PAG turned out to be highly effective in alleviating neuropathic pain. Mechanical allodynia and cold allodynia were reduced by PAG stimulation. Naloxone reversed the antiallodynic effects of ventral PAG stimulation. These results suggest that activation of the descending pain inhibition system including the ventral PAG reduces neuropathic pain syndrome and that opiates are involved in this system.
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441
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Kwon OS, Park SH, Yun BS, Pyun YR, Kim CJ. Cyclo(dehydroala-L-Leu), an alpha-glucosidase inhibitor from Penicillium sp. F70614. J Antibiot (Tokyo) 2000; 53:954-8. [PMID: 11099229 DOI: 10.7164/antibiotics.53.954] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A diketopiperazine (1) has been isolated from the culture broth of Penicillium sp. F70614 and its structure has been determined to be cyclo(dehydroala-L-Leu) by various spectroscopic analyses. This compound selectively inhibited yeast alpha-glucosidase and porcine intestinal alpha-glucosidase with IC50 values of 35 and 50 microg/ml, respectively. However, it did not show significant inhibitory effects against almond beta3-glucosidase, Aspergillus alpha-galactosidase, Escherichia coli beta-galactosidase and jack bean alpha-mannosidase.
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442
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Choi BK, Park SH, Yoo YJ, Choi SH, Chai JK, Cho KS, Kim CK. Detection of major putative periodontopathogens in Korean advanced adult periodontitis patients using a nucleic acid-based approach. J Periodontol 2000; 71:1387-94. [PMID: 11022767 DOI: 10.1902/jop.2000.71.9.1387] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Although extensive microbial analyses have been performed from subgingival plaque samples of periodontitis patients, systematic analysis of subgingival microbiota has not been carried out in a Korean population so far. The purpose of this study was to describe the prevalence of major putative periodontopathogens in Korean patients by culture-independent methods. METHODS A total of 244 subgingival plaque samples (5 sites in each participant) were taken from 29 advanced adult periodontitis (AP) patients and 20 periodontally healthy subjects. AP samples were obtained from the 4 deepest periodontal pockets (> or =6 mm probing depth [PD]) and 1 healthy site (< or =3 mm PD) in each patient. Polymerase chain reaction (PCR) of 16S ribosomal DNA (rDNA) of subgingival plaque bacteria was performed with eubacterial primers. Aliquots of PCR products were then applied on nylon membranes and hybridized with specific oligonucleotide probes labeled with digoxigenin. RESULTS All diseased sites harbored Fusobacterium sp., while Porphyromonas gingivalis, Treponema sp., and Bacteroides forsythus were detected in more than 96% of 116 diseased sites. Peptostreptococcus micros, Actinobacillus actinomycetemcomitans, and Prevotella intermedia were present in 82%, 74%, and 71% of diseased sites, respectively. In sites of periodontally healthy subjects, Fusobacterium sp. was present in the highest proportion (58%). Treponema sp., P. gingivalis, and B. forsythus were detected in 22%, 18%, and 18% of healthy sites, respectively. P. micros, P. intermedia, and A. actinomycetemcomitans were found in 8%, 2%, and 1% of healthy sites, respectively. The prevalence of the periodontopathogens, with the exceptions of Fusobacterium sp. and B. forsythus, was significantly higher in the healthy sites of periodontitis subjects than in the healthy sites of periodontally healthy subjects (P <0.05). CONCLUSIONS Using highly sensitive methods relying on 16S ribosomal RNA-based oligonucleotide probes, we confirmed the strong association of 7 putative periodontopathogens with AP patients in a Korean population. With the exceptions of Fusobacterium sp. and B. forsythus, all the periodontopathogens were significantly more associated with the healthy sites of periodontitis subjects than in the healthy sites of periodontally healthy subjects.
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Abstract
Poland's syndrome, a rare congenital anomaly characterized by pectoralis muscle defect, has been reported in association with lymphoreticular malignancies and some solid tumors. Lung cancer associated with Poland's syndrome has not been previously described. We present the first report of a case of Poland's syndrome associated with lung cancer and demonstrate the CT findings.
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Kwon OS, Byun KS, Yeon JE, Park SH, Kim JS, Kim JH, Bak YT, Kim JH, Lee CH. Detection of hepatitis A viral RNA in sera of patients with acute hepatitis A. J Gastroenterol Hepatol 2000; 15:1043-7. [PMID: 11059935 DOI: 10.1046/j.1440-1746.2000.02291.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
BACKGROUND AND AIMS The Detection of hepatitis A virus (HAV) is important for diagnosis and epidemiological studies of hepatitis A. The polymerase chain reaction (PCR) technique is a sensitive test to detect HAV-RNA in specimens. The aims of the present study were to clarify the detection rate of serum HAV-RNA by PCR and the natural history of HAV viraemia, and to determine the correlation between viraemia and the clinical characteristics in patients with acute hepatitis A. METHODS Hepatitis A virus RNA was tested in 74 serum samples which were serially collected from 27 patients with acute hepatitis A. A nested reverse transcription (RT)-PCR for HAV-RNA was performed with primer sets located at the VP1 region of the HAV genome and the PCR products were electrophoresed on a 1.5% agarose gel. RESULTS Hepatitis A virus RNA was found in 18 of 27 (67%) patients with hepatitis A. There were no significant differences between groups positive and negative for HAV-RNA in clinical and laboratory data, except the time interval between clinical onset and initial serum sampling for RT-PCR (10 +/- 6 vs 19 +/- 14 days) and the alanine aminotransferase (ALT) level at initial serum sampling for RT-PCR (1436 +/- 1416 vs 518 +/- 432 IU/L). The mean duration of HAV viraemia was 30 +/- 19 days (range, 5-59 days). The duration of HAV viraemia and duration of abnormal ALT levels from clinical onset were positively correlated (r = 0.685, P = 0.007). CONCLUSION In conclusion, HAV-RNA RT-PCR is a useful tool to detect HAV viraemia and to study the molecular epidemiology of HAV infection.
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Jung JI, Kim HH, Jung YJ, Park SH, Lee JM, Hahn ST. Mediastinal lymphadenopathy in pulmonary fibrosis: correlation with disease severity. J Comput Assist Tomogr 2000; 24:706-10. [PMID: 11045689 DOI: 10.1097/00004728-200009000-00007] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To evaluate the relationship between mediastinal lymph node enlargement and disease severity score in patients with pulmonary fibrosis. MATERIALS AND METHODS A retrospective study included 30 patients with pulmonary fibrosis: idiopathic pulmonary fibrosis (n = 25), usual interstitial pneumonia (UIP) associated with collagen vascular disease (n = 4), and UIP associated with hepatitis C (n = 1). Disease severity was determined by a computed tomography (CT) scoring system. Each patient's lobe was scored by two radiologists on a scale of 0-5 for both ground glass opacity (GGO) and fibrosis. The presence, number, and sites of enlarged nodes (short axis > or = 10 mm) were assessed. CT severity scores were compared with total number of enlarged lymph nodes (L/Ns) and short axis diameter of the largest L/N (LLN). According to each severity score, patients were divided into two groups: the GGO-predominant group (n = 10) and the fibrosis-predominant group (n = 20). Total numbers of enlarged L/Ns and short axis diameter of LLN were compared in each group. RESULTS Enlarged mediastinal L/Ns were present in 86%. Total severity score, GGO score, and fibrosis score strongly correlated with total number of enlarged L/Ns (p<0.05). Total severity score and GGO score correlated well with short axis diameter of LLN; however, the fibrosis score did not correlate with the short axis diameter of LLN. In respect to total number of enlarged L/Ns, the difference between the GGO group and fibrosis group was not apparent. In respect to the short axis diameter of LLN, the GGO group LLN was larger in diameter than the fibrosis group LLN (p<0.05). CONCLUSION The greater the severity score of pulmonary fibrosis, the larger the total number of enlarged L/Ns. Those patients with more GGO had larger lymph nodes.
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Sohn SK, Baek JH, Kim DH, Jung JT, Kwak DS, Park SH, Suh JS, Lee KB. Successful allogeneic stem-cell transplantation with prophylactic stepwise G-CSF primed-DLIs for relapse after autologous transplantation in mantle cell lymphoma: a case report and literature review on the evidence of GVL effects in MCL. Am J Hematol 2000; 65:75-80. [PMID: 10936869 DOI: 10.1002/1096-8652(200009)65:1<75::aid-ajh14>3.0.co;2-l] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Mantle cell lymphoma (MCL) is a distinctive clinicopathologic entity and represents 2-8% of all non-Hodgkin's lymphomas. The median survival of patients with MCL is only 3 years, and none of the available conventional chemotherapy regimens appears curative. Encouraging results have been reported with high-dose chemotherapy with autologous stem-cell transplantation (autoSCT). However, a plateau in disease-free survival was not observed in relapsed MCL on the autoSCT trials. Promisingly, alloSCT appears to induce durable remissions via a graft-versus-lymphoma (GVL) effect. Donor lymphocyte infusions (DLIs), by virtue of a GVL effect, have been shown to induce durable remissions in a few cases with refractory MCL that recur after alloSCT. In this article, we review the literature on the evidence of the GVL effects in MCL and describe a patient with relapsed MCL shortly after high-dose chemotherapy with autoSCT. The patient was then successfully treated with Bu/Cy/VP-16 for an alloSCT followed by DLIs in a stepwise fashion. MNCs > 10 x 10(8)/kg were collected by two large-volume leukaphereses from the donor. Harvested stem cells from the 2(nd) day were cryopreserved for the future use as prophylactic DLIs to be given in a stepwise fashion. Cyclosporin and methotrexate were used for GVHD prophylaxis. He had achieved only a partial response by D+64 post transplant. G-CSF-primed cryopreserved DLIs were then infused on D+64 and D+92 to enhance the GVL effect. Grade 3 intestinal GVHD developed 20 days after the 2(nd) DLI and was partially controlled with the combination of cyclosporin, prednisone, and mycophenolate mofetil. Clinical complete remission was observed at D+112, and maintained until the last follow-up day (D+615). Our findings suggest that alloSCT followed by prophylactic DLIs may offer a curative approach to refractory MCL.
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Shin BS, Choi SK, Smith I, Park SH. Analysis of tnrA alleles which result in a glucose-resistant sporulation phenotype in Bacillus subtilis. J Bacteriol 2000; 182:5009-12. [PMID: 10940050 PMCID: PMC111386 DOI: 10.1128/jb.182.17.5009-5012.2000] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacillus subtilis cells cannot sporulate in the presence of catabolites such as glucose. During the analysis of Tn10-generated mutants, we found that deletion of the C-terminal region of the tnrA gene, which encodes a global regulator that positively regulates a number of genes in response to nitrogen limitation, results in a catabolite-resistant sporulation phenotype. Analyses of nrg-lacZ and nasB-lacZ, which are activated by TnrA under nitrogen limitation, showed that C-terminally truncated TnrA activates nitrogen-regulated genes constitutively. The relief of catabolite repression of sporulation may result from the uncontrolled expression of the TnrA-regulated genes.
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Abstract
CD1, a conserved family of major histocompatibility (MHC)-like glycoproteins in mammals, specializes in capturing lipid rather than peptide antigen for presentation to T lymphocytes. The principles and mechanisms of this newly discovered immune strategy differ markedly from those governing classical MHC-peptide presentation. They might be exploited for the design of new lipid-based microbial vaccines and adjuvants.
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Kim DE, Park SH, Kim SK, Nam HW, Lee YS, Chung JK, Roh JK. Hypoglycemia-induced cerebellar dysfunction and quantitative positron emission tomography study. Neurology 2000; 55:418-22. [PMID: 10932278 DOI: 10.1212/wnl.55.3.418] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To describe an unusual case of hypoglycemia-induced bilateral cerebellar dysfunction. BACKGROUND The cerebellum is known to be resistant to hypoglycemia, and selective cerebellar dysfunction caused by hypoglycemia has not been reported. Previous studies showed that the ratio between the rate constants for glucose uptake and phosphorylation (K1 and k3) is reversed in the cerebellum compared with the cerebral cortex; higher K1 in the cerebellum and higher k3 in the cerebral cortex. METHODS Quantitative dynamic PET scanning with labeled fluorodeoxyglucose (18F-FDG) was performed to prove altered glucose kinetics in the cerebellum of a patient who presented with episodic cerebellar dysfunction associated with hypoglycemia. Four control subjects underwent the same study. RESULTS The ratio between K1 and k3 was not reversed in the cerebellum of our patient (K1 = 0.082, k3 = 0.192). On the contrary, the ratio was reversed in the control subjects (mean K1 = 0.109, mean k3 = 0.080). In addition, the patient's cerebellar metabolic rate of glucose (rCMRglu = 27.9 micromol/100 g/minute) and the rate constant of glucose egress (k2 = 0.543) were relatively increased compared with those of control subjects (mean rCMRglu = 21.9 micromol/100 g/minute, mean k2 = 0.352). CONCLUSIONS In a case of episodic bilateral cerebellar dysfunction caused by hypoglycemia, quantitative dynamic PET study demonstrated decreased glucose uptake-to-utilization ratio and increased leak of glucose in the cerebellum. The cerebellum is not invariably resistant to hypoglycemia.
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Kim JE, Kim CJ, Park IA, Kim WH, Seo JW, Jang JJ, Kim CW, Park SH, Lee HS, Chi JG, Kim YI, Ham EK. Clinicopathologic study of Castleman's disease in Korea. J Korean Med Sci 2000; 15:393-8. [PMID: 10983686 PMCID: PMC3054666 DOI: 10.3346/jkms.2000.15.4.393] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Castleman's disease represents an atypical lymphoproliferative disorder, infrequently associated with various immunologic abnormalities or subsequent development of malignancy such as Kaposi sarcoma, malignant lymphoma and plasmacytoma. Its clinicopathologic features depend on various etiologic factors such as Kaposi sarcoma herpesvirus (KSHV), oversecretion of IL-6, adhesion molecule and follicular dendritic cell dysplasia, etc. To investigate the relationship of Castleman's disease (CD) and the above factors, we reviewed 22 cases of CD. Four cases of KSHV positive CD were detected, all multicentric, plasma cell type, and these cases displayed prominent vascular proliferation, characteristic 'Kaposi-like lesion'. IL-6 and CD54 positive mononuclear cells were scattered in interfollicular areas of KSHV positive cases. Follicular dendritic cell hyperplasia, vascular proliferation, expression of IL-6 and CD54 did not show any significant difference between solitary vs multicentric type, and plasma cell type vs hyaline vascular type. Our study suggests that KSHV positive CD reveals unique pathologic features, and the probable relationship of KSHV and IL-6 and CD54 is discussed.
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