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Woo ER, Kim WS, Kim YS. Virus-cell fusion inhibitory activity for the polysaccharides from various Korean edible clams. Arch Pharm Res 2001; 24:514-7. [PMID: 11794525 DOI: 10.1007/bf02975155] [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: 10/21/2022]
Abstract
In order to find potent virus-cell fusion inhibitory components from Korean edible clams, thirteen prepared polysaccharides were introduced to syncytia formation inhibition assay, which is based on the interaction between the HIV-1 envelope protein gp120/41 and the cellular membrane protein CD4 of T lymphocytes. Among them, Meretrix petechialis showed a potent virus-cell fusion inhibitory activity. Fusion index (FI) and percent (%) fusion inhibition of the polysaccharide of this clam were 0.21 +/- 0.02, and 67.52 +/- 4.09 at 100 microg/ml, respectively. It exhibited almost equivalent virus-cell fusion inhibitory activity to that of dextran sulfate which was used as a standard control.
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Dai G, Su P, Allison GE, Geller BL, Zhu P, Kim WS, Dunn NW. Molecular characterization of a new abortive infection system (AbiU) from Lactococcus lactis LL51-1. Appl Environ Microbiol 2001; 67:5225-32. [PMID: 11679349 PMCID: PMC93294 DOI: 10.1128/aem.67.11.5225-5232.2001] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
This study reports on the identification and characterization of a novel abortive infection system, AbiU, from Lactococcus lactis. AbiU confers resistance to phages from the three main industrially relevant lactococcal phage species: c2, 936, and P335. The presence of AbiU reduced the efficiency of plaquing against specific phage from each species as follows: 3.7 x 10(-1), 1.0 x 10(-2), and 1.0 x 10(-1), respectively. abiU involves two open reading frames, abiU1 (1,772 bp) and abiU2 (1,019 bp). Evidence indicates that AbiU1 is responsible for phage resistance and that AbiU2 may downregulate phage resistance against 936 and P335 type phages but not c2 type phage. AbiU appeared to delay transcription of both phage 712 and c2, with the effect being more marked on phage c2.
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Kim WS, Hildebrand M, Jock S, Geider K. Molecular comparison of pathogenic bacteria from pear trees in Japan and the fire blight pathogen Erwinia amylovora. MICROBIOLOGY (READING, ENGLAND) 2001; 147:2951-9. [PMID: 11700346 DOI: 10.1099/00221287-147-11-2951] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Several strains of the genus Erwinia, which were isolated in Japan from pear trees with necrotic symptoms that resembled fire blight, and tentatively identified as Erwinia amylovora, were reinvestigated for their relationship to the fire blight pathogen. These isolates produced ooze on slices of immature pears and were mucoid on MM2Cu agar plates, but did not synthesize levan and did not give the expected PCR signals with several primer pairs specific for Erwinia amylovora. The isolates tested positive with PCR primers designed to detect the novel pear pathogen Erwinia pyrifoliae, which was isolated from Nashi pear trees in South Korea. The nucleotide sequence analysis of a DNA fragment preceding the gene cluster for exopolysaccharide synthesis revealed a closer relationship to Erwinia pyrifoliae than to Erwinia amylovora. Plasmid profiles, protein patterns and genomic DNA analysed by PFGE after XbaI and SpeI digestion were different than Erwinia amylovora. Experiments with strains of Erwinia amylovora isolated from raspberry (Rubus sp.), Erwinia mallotivora and Enterobacter pyrinus also did not reveal a relationship between these bacteria and the Japanese Erwinia strains. The latter are not identical to Erwinia pyrifoliae, but possess many similar features to this pathogen that causes Asian pear blight. It is concluded that pathogenic bacteria isolated in Japan from pear trees with symptoms resembling fire blight are possibly different from Erwinia amylovora.
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Kim WS, Perl L, Park JH, Tandianus JE, Dunn NW. Assessment of stress response of the probiotic Lactobacillus acidophilus. Curr Microbiol 2001; 43:346-50. [PMID: 11688799 DOI: 10.1007/s002840010314] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Different aspects of stress response of Lactobacillus acidophilus were investigated. First, the sublethal and lethal levels of bile, heat, and NaCl stresses were determined. They were 0.05% and 0.5% (bile), 53 degrees C and 60 degrees C (heat), and 2% and 18% (NaCl), respectively. To evaluate the effect of each stress at log phase, log-phase cultures were challenged directly with the lethal level of each stress (control) and were compared to log-phase cultures that were pre-exposed to the sublethal level prior to the exposure at the lethal level (test). Some, if not most, of the cells were killed in the control cultures against each of the three stresses. However, in the test cultures, the number of cells that had survived increased significantly. It appears that L. acidophilus is capable of displaying adaptive response to stress. The adaptive response to one stress was also shown to provide cross-protection against different stresses tested. The effect of each stress on stationary-phase cultures was also investigated. In contrast to log-phase culture, stationary-phase culture was inherently resistant to stress.
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Ma DH, Chen JK, Kim WS, Hao YX, Wu HC, Tsai RJ, Hwang DG, Zhang F. Expression of matrix metalloproteinases 2 and 9 and tissue inhibitors of metalloproteinase 1 and 2 in inflammation-induced corneal neovascularization. Ophthalmic Res 2001; 33:353-62. [PMID: 11721189 DOI: 10.1159/000055693] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
PURPOSE Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinase (TIMPs) have been linked to the angiogenic process in general. In order to understand the potential roles of MMP-2, MMP-9 and TIMPs in the corneal neovascularization process, we examined the expression and activities of MMP-2, MMP-9 and TIMPs during the course of cauterization-induced corneal neovascularization in a rat model. METHODS Neovascularization of rat corneas was induced by silver nitrate cauterization. The expression of MMP-2, MMP-9, TIMP-1 and TIMP-2 was examined by immunohistochemistry and RT-PCR. The protein activities of MMPs and TIMPs were compared in pre- and postcauterization corneas by gelatin zymography and reverse zymography, respectively. RESULTS MMP-2, TIMP-1 and TIMP-2 immunoreactivities were expressed in normal corneas, predominantly in the corneal epithelium. After injury, immunoreactivities of both MMPs and TIMPs were increased, notably in the healing corneal epithelium, infiltrating inflammatory cells, stromal fibroblasts and ingrowing vascular endothelial cells. The increase in gross MMP-2 enzymatic activity paralleled the maximal vascular ingrowth on day 4, while the gross MMP-9 enzymatic activity rose immediately on day 1, then decreased steadily, which paralleled the magnitude of inflammatory cell infiltration. The immunoreactivity of MMPs/TIMPs decreased significantly 2 weeks after cauterization. On day 35, MMP-2, TIMP-1 and TIMP-2 staining was seen only in corneal epithelium and vascular endothelial cells. Both the RT-PCR and reverse zymography results revealed a more constant expression of TIMP-2, while the TIMP-1 expression appeared to be more inducible. CONCLUSION MMPs as well as TIMPs were upregulated in cauterization-induced corneal neovascularization, suggesting that both may participate in extracellular matrix remodeling in the corneal wound healing, inflammation and neovascularization processes.
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Lim CM, Kim EK, Lee JS, Shim TS, Lee SD, Koh Y, Kim WS, Kim DS, Kim WD. Comparison of the response to the prone position between pulmonary and extrapulmonary acute respiratory distress syndrome. Intensive Care Med 2001; 27:477-85. [PMID: 11355115 DOI: 10.1007/s001340000848] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
OBJECTIVES To determine whether the response to the prone position differs between acute respiratory distress syndrome (ARDS) resulting from a pulmonary cause (ARDSp) and that from an extrapulmonary cause (ARD-Sexp). DESIGN AND SETTING Prospective observational study in a medical ICU of a university-affiliated hospital. SUBJECTS A consecutive series of 31 patients with ARDSp and 16 with ARDSexp within 3 days of onset of ARDS. INTERVENTION Prone position for at least 2 h. MEASUREMENTS AND RESULTS In ARDSp, compared with the supine position (121 +/- 49 mmHg), PaO2/FIO2 was not increased after 0.5 h but was increased after 2 h in the prone position (158 +/- 60 mmHg). In ARDSexp, compared with the supine position (106 +/- 53 mmHg), PaO2/FIO2 was increased after 0.5 h (155 +/- 91 mmHg), but was not further changed after 2 h. Marked oxygenation response (increase in PaO2/FIO2 > 40% from baseline) after 0.5 h was 23% in ARDSp and 63% in ARDSexp, and that after 2 h was 29% and 63%, respectively. Static respiratory compliance decreased in the prone position in ARDSexp (30 +/- 11 ml/cmH2O at baseline, 27 +/- 11 after 0.5 h and 25 +/- 9 after 2 h) but not in ARDSp. Consolidation score as determined on the first chest radiography taken in the prone position decreased to a greater degree in ARDSexp (-2.4 +/- 4.1) than in ARDSp (0.3 +/- 4.1). CONCLUSION Pulmonary ARDS and extrapulmonary ARDS in their early stages respond differently to the prone position with regard to the time course of oxygenation, respiratory mechanical behaviour, and radiographic change. These findings suggest that the early pathophysiology of ARDS differs according to the type of primary insult to the lung.
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Lee JH, Chun YG, Lee IC, Tuder RM, Hong SB, Shim TS, Lim CM, Koh Y, Kim WS, Kim DS, Kim WD, Lee SD. Pathogenic role of endothelin 1 in hemodynamic dysfunction in experimental acute pulmonary thromboembolism. Am J Respir Crit Care Med 2001; 164:1282-7. [PMID: 11673223 DOI: 10.1164/ajrccm.164.7.2011011] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The plasma endothelin-1 (ET-1) level is elevated in patients with acute pulmonary thromboembolism (APE). Whether ET-1 is a pathogenic mediator or a simple marker of APE is not known. We investigated the role of ET-1 in hemodynamic dysfunction in APE through evaluating the effects of ET(A) receptor antagonist in an experimental APE model. We also examined ET-1 expression in embolized lungs. In a canine autologous blood clot pulmonary embolism model, ET(A) receptor antagonist ZD2574 (10 mg/kg, intravenous; ZD2574 group; n = 6) or vehicle (control group; n = 5) was administered. Hemodynamic and gas exchange parameters and plasma levels of ET-1 were serially measured. Prepro-ET-1 mRNA expression and the distribution of ET-1 peptide in lung tissues were also examined. With ZD2574 pulmonary arterial pressure and pulmonary vascular resistance significantly decreased, and were lower compared with the control group. The decrease in cardiac output was also less in the ZD2574 group. Plasma ET-1 levels increased after embolization. Prepro-ET-1 mRNA expression increased in embolized lungs and ET-1 peptide expression also increased in embolized lungs, particularly in the muscular pulmonary arteries, compared with normal lungs. These findings suggest that ET-1 partially contributes to hemodynamic derangements of APE, and that ET(A) receptor antagonists might constitute a useful therapeutic tool for APE.
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Ren J, Park JH, Dunn NW, Kim WS. Sequence and stress-response analyses of the DNA mismatch repair gene hexA in Lactococcus lactis. Curr Microbiol 2001; 43:232-7. [PMID: 11683355 DOI: 10.1007/s002840010293] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The DNA mismatch repair gene hexA was identified in Lactococcus lactis by PCR amplification by using a pair of primers homologous to the DNA-binding Dps protein. The gene in its entirety, including the regulatory regions, was sequenced, by using a strategy of chromosomal walking based on two PCR protocols. The open reading frame of 2526 bp was preceded by a strong ribosome-binding site (AGGAAG) and was followed by a potential transcription terminator (hairpin loop structure). The 5' terminus of the hexA mRNA was located 135 bp upstream of the start codon, and putative -10 and -35 regions were identified. The deduced amino acid sequence revealed two motifs, the ATP/GTP-binding site (P-loop) and the "MutS family signature". The hexA promoter was cloned into pMU1327, which contained a promoter-less CAT reporter gene, and the promoter activity was examined under oxidative-stress conditions. It appears that the promoter activity is down-shifted by H2O2 at 4 mM.
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Park JH, Na JO, Kim EK, Lim CM, Shim TS, Lee SD, Kim WS, Kim DS, Kim WD, Koh Y. The prognosis of respiratory failure in patients with tuberculous destroyed lung. Int J Tuberc Lung Dis 2001; 5:963-7. [PMID: 11605892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
Abstract
SETTING The medical intensive care unit of a tertiary referral hospital. OBJECTIVE To determine the prognosis of patients whose lungs are damaged by previous and/or present tuberculosis infection and who have subsequently been presented with acute respiratory failure requiring mechanical ventilation. DESIGN A consecutive series of 38 patient cases with retrospective data analysis. RESULTS Pulmonary function test results for tests performed within the previous year were made available in 21 of the 38 cases (55%). These showed a mean (+/- SD) forced vital capacity (FVC) of 1.52 +/- 0.46 L (41.0 +/- 14.5% predicted), a forced expiratory volume/second (FEV1) of 0.77 +/- 0.18 L (29.3 +/- 13.6% predicted), and an FEV1/FVC ratio of 55.1 +/- 16.2%. The acid-fast bacilli (AFB) positive group had a significantly higher mortality and more severe lung destruction when compared with the AFB-negative group. Patients with positive AFB were significantly more hypocapnic than those with negative AFB (6.4 +/- 2.7 vs. 9.3 +/- 3.9 kPa, P = 0.020). In multivariate analysis, the level of PaCO2 on admission was identified as the only significant prognostic index (OR 0.76, 95%CI 0.60-0.96). CONCLUSION Patients with positive AFB smears or cultures may have higher mortality rates than those with negative AFB in the tuberculosis destroyed lung patients with acute respiratory failure. A higher PaCO2 measurement could indicate a better survival rate in this group of patients.
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Lee JE, Kim DY, Ahn YC, Lim DH, Huh SJ, Shin SS, Kim WS, Kang WK, Nam DH, Lee JI, Kim JH. Combined Chemotherapy and Radiotherapy for Primary CNS Lymphoma. Cancer Res Treat 2001; 33:398-403. [PMID: 26680814 DOI: 10.4143/crt.2001.33.5.398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
PURPOSE This study was performed in order to evaluate the effectiveness of combined chemotherapy and radiotherapy (RT) in primary central nervous system lymphoma (PCNSL). MATERIALS AND METHODS From January 1995 to August 1999, 21 patients with a diagnosis of PCNSL were treated with combined chemotherapy and radiotherapy. Their median age was 47 years with range of 19 to 78 years. Twelve patients were male and nine patients were female. All patients were immunocompetent and they had no evidence of systemic lymphoma. All patients underwent placement of an Ommaya reservoir and recieved a combination regimen using pre-RT systemic and intra-Ommaya methotrexate (MTX), 40 Gy whole-brain RT with a 14.4 Gy boost, and 2 courses of post-RT high-dose cytarabine. The median follow-up period of all patients and survived patients were 22 months and 36 months, respectively. RESULTS The median overall survival duration was 21 months and the overall two- and four-year survival rates were 51% and 43%, respectively. Complete response (CR), partial response, stable disease, and progressive disease were achieved in 12, 3, 1, and 5 patients, respectively. All nine patients without CR expired within 1-31 months (median 6 months). Two patients among the patients with CR developed recurrence after 13 and 14 months, respectively. The location of recurrent disease was within the port of radiation boost. Survival was influenced by age, performance status, and CR. There was one episode of MTX neurotoxicity and hepatotoxicity,respectively. CONCLUSION Combined chemotherapy and radiotherapy was an effective treatment for PCNSL, and was associated with a minimum toxicity. However, we must pay attention to the recurrence and late toxicity, particularly within two years following treatment.
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Kim WS, Park JH, Ren J, Su P, Dunn NW. Survival response and rearrangement of plasmid DNA of Lactococcus lactis during long-term starvation. Appl Environ Microbiol 2001; 67:4594-602. [PMID: 11571161 PMCID: PMC93208 DOI: 10.1128/aem.67.10.4594-4602.2001] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The survival response of Lactococcus lactis during long-term starvation was investigated. The cells were cultured with different levels of glucose (the sole energy source) and either were kept in the resultant spent medium or transferred to fresh medium (without glucose) for up to 2 years. The survival of the cells during starvation was not dependent on the nature of transition phase, as expected, but on the nature of medium in which the cells were kept. The proliferation of cells, despite the apparent lack of glucose, could have been due to some cells being able to utilize the small amounts of peptides still present in the spent medium or to use energy sources provided by the breakup of dead cells. The 1- and 2-year-old cultures contained cells with vastly changed morphotypes. When these isolates were examined, it was revealed that the original plasmids present in the parent were rearranged in a certain way, and an entirely new plasmid was generated. Changes were also evident in the chromosomal DNA and in gene expression. Furthermore, all of the isolates exhibited a growth advantage relative to the parent cells when grown in energy-limiting media. When they were tested against different types of stresses, they exhibited a higher resistance against the bile salt and hydrogen peroxide stresses compared to the parent. Because of the similar changes observed in the 2-year-old isolates, a similar survival strategy may be operational in those cells that survive for that length of time.
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Kang J, Lee CH, Haam S, Koo KK, Kim WS. Studies on the overall oxygen transfer rate and mixing time in pilot-scale surface aeration vessel. ENVIRONMENTAL TECHNOLOGY 2001; 22:1055-1068. [PMID: 11816768 DOI: 10.1080/09593332208618215] [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
An aerated vessel with Simcar type surface aerator was studied to estimate its significant performance characteristics i.e., oxygen transfer rate, mixing time and power consumption. The oxygen transfer and mixing characteristics were investigated with variations in the operating variables such as rotational speed, diameter, bottom clearance of impeller, liquid height and power consumption in single and dual impeller systems. The bottom clearance of the top impeller was found to affect largely the capacity of the impeller by varying the quantity of liquid loaded to it. It was also ensured that surface aeration caused a slight increase in mixing time compared to it under ungassed conditions. The dual impeller system was employed for the purpose of improving oxygen transfer and mixing at TH < 1 varying the types and the bottom clearance of thelower impeller. However, the oxygen transfer rate was independent of the lower impeller mainly depending on the capacity of the top impeller though mixing time was sharply reduced by the lower impeller. The effect of the bottom clearance of the lower impeller was related to the liquid flow pattern inside the vessel, which was presented by computational fluid dynamics (CFD). The oxygen transfer rate and the mixing time were correlated with power consumption within reliable error range.
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Lee JW, Kim IO, Kim WS, Yeon KM, Lee HJ, Hwang YS. Herpes simplex encephalitis: MRI findings in two cases confirmed by polymerase chain reaction assay. Pediatr Radiol 2001; 31:619-23. [PMID: 11512000 DOI: 10.1007/s002470100508] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Herpes simplex virus (HSV) type I causes a fulminant necrotising meningoencephalitis distinguished from other encephalitides by its focal and often haemorrhagic nature. Specific antiviral therapy with acyclovir can significantly improve the prognosis. We present MRI findings of two cases of herpes simplex encephalitis (HSE) confirmed by PCR analysis, focusing on the serial changes after acyclovir therapy: gyral swelling, high signal intensity on T2-weighted images in the subfrontal region, temporal lobe and insula in the initial stage, then regional extension with enhancement and haemorrhage despite appropriate acyclovir therapy, and finally encephalomalacia and brain atrophy.
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Kwon BK, Han KH, Han KY, Ju SM, Hwang SG, Jeon BH, Han DM, Kim WS. Molecular cloning of kpcA gene encoding a Kex2p-like endoprotease from Aspergillus nidulans. Mol Cells 2001; 12:142-7. [PMID: 11561725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
Abstract
We cloned and sequenced a gene, kpcA (Kex2p-like proprotein convertase A), from a genomic library of Aspergillus nidulans. The kpcA gene encodes an 820-residue protein, named KpcA, which contains a putative subtilisin-like catalytic domain (residues 136-466) homologous to that of the subtilisin serine protease family. KpcA shows 56, 73, and 47% amino acid identities with Saccharomyces cerevisiae Kex2p, Aspergillus niger KexB, and mouse furin within the subtilisin-like catalytic domain, respectively. The sequences around the proposed active site Asp, His, and Ser residues of KpcA are similar to those of other Kex2p family members. The KpcA mRNA transcript with an expected size of approximately 2.8 kb was detected in A. nidulans. The substrate specificity of KpcA, expressed in CHO cells, is similar to that of A. niger KexB and yeast Kex2p. We conclude that KpcA is a resident Kex2p-like proprotein that processes endoprotease in A. nidulans.
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Kwon JW, Kim IO, Cheon JE, Kim WS, Chi JG, Wang KC, Yeon KM. Cerebellopontine angle ganglioglioma: MR findings. AJNR Am J Neuroradiol 2001; 22:1377-9. [PMID: 11498430 PMCID: PMC7975207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
We present a case of cerebellopontine (CP) angle ganglioglioma in a young child with developmental delay and no trigeminal nerve symptoms. MR imaging demonstrated a mass of homogeneous low signal intensity in the left CP angle on T1-weighted images with no enhancement with gadolinium, and of relatively homogeneous high signal intensity on T2-weighted images.
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Lee SD, Lee DS, Chun YG, Shim TS, Lim CM, Koh Y, Kim WS, Kim DS, Kim WD. Cigarette smoke extract induces endothelin-1 via protein kinase C in pulmonary artery endothelial cells. Am J Physiol Lung Cell Mol Physiol 2001; 281:L403-11. [PMID: 11435215 DOI: 10.1152/ajplung.2001.281.2.l403] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We examined the mechanism of endothelin (ET)-1 regulation by cigarette smoke extract (CSE) and the effect of platelets on CSE-induced stimulation of ET-1 gene expression in human and bovine pulmonary artery endothelial cells (PAECs). Our data show that CSE (1%) induces ET-1 gene expression (after 1 h) and ET-1 peptide synthesis (after 4 h) in bovine PAECs. The induction of preproET-1 mRNA level was due to de novo transcription, and new protein synthesis was not required for this induction. The protein kinase C inhibitors staurosporine (10(-8) mol/l) and calphostin C (10(-7) mol/l) abolished the induction of ET-1 gene expression by CSE in bovine and human PAECs. Although a lower concentration of platelets (10(6) cells/ml in bovine PAECs; 10(7) cells/ml in human PAECs) did not significantly alter ET-1 gene expression in PAECs, incubation of platelets with CSE (1%) and PAECs produced a significant increase in preproET-1 mRNA and ET-1 peptide compared with the values in the presence of CSE (1%) alone. CSE (1%) induced platelet aggregation and increased the expression of platelet membrane glycoproteins ex vivo. Thus our data suggest that CSE stimulates ET-1 gene expression via PKC in PAECs. CSE and platelets showed a synergistic effect on ET-1 gene expression, possibly through the activation of platelets by CSE.
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Kim WS, Kim MM, Choi HJ, Yoon SS, Lee MH, Park K, Park CH, Kang WK. Phase II study of high-dose lovastatin in patients with advanced gastric adenocarcinoma. Invest New Drugs 2001; 19:81-3. [PMID: 11291836 DOI: 10.1023/a:1006481423298] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Lovastatin, an inhibitor of mevalonate synthesis, demonstrated in vitro antitumor activity against a variety of human cancer cells, especially in gastric adenocarcinoma cells at pharmacologically achievable concentrations. To determine the antitumor activity of this drug in advanced measurable gastric adenocarcinoma as well as to assess the toxicities and the pharmacokinetic features, we carried out a phase II study of high-dose lovastatin. Patients received lovastatin 35 mg/kg/day for 7 consecutive days, with ubiquinone (60 mg qid p.o.) to prevent rhabdomyolysis. The treatment was repeated every 28 days. From March 1996 to January 1997, 16 patients (median age, 57 years; range, 34-68) were entered into the study, 14 of whom were evaluated for response and toxicity. No patient achieved a response. A total of 28 cycles were administered. The median number of cycles was 2 (range, 1 to 4). Anorexia was the most common toxicity (64%), but decreased oral intake was observed only in 3 cycles. Two patients developed myalgia with elevated muscle enzyme. When used in this dosage and schedule, lovastatin does not appear to be effective for patients with advanced gastric adenocarcinoma.
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You JO, Park SB, Park HY, Haam S, Chung CH, Kim WS. Preparation of regular sized Ca-alginate microspheres using membrane emulsification method. J Microencapsul 2001; 18:521-32. [PMID: 11428680 DOI: 10.1080/02652040010018128] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Monodisperse Ca-alginate microspheres were prepared using the membrane emulsification method. Three ionic types of drugs (anionic, cationic and non-ionic) were incorporated into the microspheres, and the effects of sodium alginate concentration and the pressure applied during the dispersing process on the properties of the microspheres were examined. Monodisperse microspheres were obtained when the concentration of alginate solution was 2 wt% and the pressure applied was 0.4 x 10(5) Pa. The mean size of microspheres was approximately 4 microm. Lidocaine x HCl (cationic), sodium salicylate (anionic) and 4-acetamidophenol (non-ionic) were selected as ionic model drugs and included in the alginate microspheres. Lidocaine x HCl (cationic drug) release was more retarded than that of the anionic drug, because of the electrostatic attraction between the negative charge of the ionized carboxyl group in the alginate chain and the positive charge of the cationic drug. In acidic release medium, a slow release was observed due to the low swelling characteristic and the increased viscosity of alginate, regardless of ionic type of drug.
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Koh Y, Lee YM, Lim CM, Lee SS, Shim TS, Lee SD, Kim WS, Kim DS, Kim WD. Effects of heat pretreatment on histopathology, cytokine production, and surfactant in endotoxin-induced acute lung injury. Inflammation 2001; 25:187-96. [PMID: 11403210 DOI: 10.1023/a:1011040515262] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
To determine the effect of heat stress on histopathology of acute lung injury (ALI) caused by administration of lipopolysaccharide (LPS), and to determine the roles of tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, interferon (IFN)-gamma, IL-10 and surfactants in heat-induced tolerance to ALI, we administered either saline or LPS (3 mg/kg of body weight) intravenously to male Sprague-Dawley rats without and with heat pretreatment. Five hours after LPS or saline treatment (23 h after heat-pretreatment), samples were obtained. We found that the histopathologic features of LPS-induced ALI were attenuated by heat-pretreatment. Heat-pretreatment did not decrease the elevated plasma or BAL fluid levels of TNF-alpha, IL-1beta, and IFN-gamma by LPS. The plasma level of IL-10 in LPS-treated rats with heat-pretreatment, however, was increased compared to that of LPS-treated rats without heat-pretreatment (P = 0.001). There were no differences in the BAL fluid concentrations of light or heavy density pulmonary surfactant phospholipids depending on heat-pretreatment in LPS-treated rats. These observations suggest that IL-10 might play a role in decreasing LPS-induced acute lung injury after heat-pretreatment.
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Lim CM, Koh Y, Park W, Chin JY, Shim TS, Lee SD, Kim WS, Kim DS, Kim WD. Mechanistic scheme and effect of "extended sigh" as a recruitment maneuver in patients with acute respiratory distress syndrome: a preliminary study. Crit Care Med 2001; 29:1255-60. [PMID: 11395617 DOI: 10.1097/00003246-200106000-00037] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE To devise a new form of sigh ("extended sigh") capable of providing a sufficient recruiting pressure x time, and to test it as a recruitment maneuver in patients with acute respiratory distress syndrome. DESIGN Prospective uncontrolled clinical trial. SETTING Medical intensive care unit of a university-affiliated hospital. PATIENTS Twenty consecutive patients diagnosed with acute respiratory distress syndrome (18 men, 2 women, age 59 +/- 10 yrs). INTERVENTIONS From baseline settings of tidal volume (Vt) 8 mL/kg and positive end-expiratory pressure (PEEP) 10 cm H2O on volume control mode with the high pressure limit at 40 cm H2O, the Vt-PEEP values were changed to 6-15, 4-20, and 2-25, each step being 30 secs (inflation phase). After Vt-PEEP 2-25, the mode was switched to continuous positive airway pressure of 30 cm H2O for a duration of 30 secs (pause), after which the baseline setting was resumed following the reverse sequence of inflation (deflation phase). This extended sigh was performed twice with 1 min of baseline ventilation between. MEASUREMENTS AND RESULTS Airway pressures and hemodynamic parameters were traced at each step during the extended sigh. Arterial blood gases and physiologic parameters were determined before the extended sigh (pre-extended sigh), at 5 mins after two extended sighs (post-extended sigh), and then every 15 mins for 1 hr. In our average patient, the recruiting pressure x time of the inflation phase was estimated to be 32.8-35.4 cm H2O x 90 secs. Compared with the inflation phase, inspiratory pause pressure of the deflation phase was lower at Vt-PEEP 6-15 (28.9 +/- 2.7 cm H2O vs. 27.3 +/- 2.8 cm H2O) and 4-20 (31.8 +/- 2.9 cm H2O vs. 31.1 +/- 2.9 cm H2O; both p <.05). Compared with pre-extended sigh, Pao2 (81.5 +/- 15.3 mm Hg vs. 104.8 +/- 25.0 mm Hg; p <.001) and static respiratory compliance both increased post-extended sigh (27.9 +/- 7.9 mL/cm H2O vs. 30.2 +/- 9.7 mL/cm H2O; p =.009). Improvement in these parameters was sustained above pre-extended sigh for the duration of the study. Major hemodynamic or respiratory complications were not noted during the study. CONCLUSION We present a new form of sigh (i.e., extended sigh) capable of achieving an augmented recruiting pressure x time through a prolonged inflation on a gradually increased end-expiratory pressure. In view of the sustained effect and absence of major complications in our patients, extended sigh could be a useful recruitment maneuver in acute respiratory distress syndrome.
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Lee WS, Lee KS, Kim KH, Ryoo BY, Kim WS, Kang WK, Kang YK, Heo DS, Bang YJ, Kim NK. A Phase II Trial of UFT-E and Oral Leucovorin in Advanced Colorectal Cancer. Cancer Res Treat 2001; 33:225-8. [PMID: 26680789 DOI: 10.4143/crt.2001.33.3.225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
PURPOSE To determine the efficacy and toxicity of UFT-E plus oral calcium leucovorin in the treatment of patients with advanced colorectal cancer. MATERIALS AND METHODS Forty-three patients with advanced, bidimensionally measurable colorectal adenocarcinoma were enrolled in the trial. No patients had received prior palliative chemotherapy. The patients that had received previous adjuvant chemotherapy were enrolled when more than 6 months had elapsed after the completion of adjuvant therapy. Patients were treated with 300 mg/m2/day of UFT-E (tegafur-based) plus 90 mg/day of leucovorin administered orally in three divided daily doses, every 8 hours for 28 days followed by a 7-day rest period. Response was evaluated after two or three courses of therapy. RESULTS Thirty-six of forty-three patients were evaluable for response; seven dropped out due to infection, toxicity and patients' refusal. Ten patients had partial responses and one patient complete response (response rate, 31%; 95% confidence interval, 16~46%). The median response duration for the UFT-E plus leucovorin regimen was 28 weeks. Grade III toxicity was seen in one case, with diarrhea. CONCLUSION This oral regimen proved effective and well tolerated. This schema also avoided inconveniences, such as hospitalization and the use of infusion pumps, which are associated with 5-FU infusion regimens. The regimen used showed minimal toxicity, especially in the upper digestive tract, with good patient compliance.
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Park J, Kim DS, Shim TS, Lim CM, Koh Y, Lee SD, Kim WS, Kim WD, Lee JS, Song KS. Lung cancer in patients with idiopathic pulmonary fibrosis. Eur Respir J 2001; 17:1216-9. [PMID: 11491167 DOI: 10.1183/09031936.01.99055301] [Citation(s) in RCA: 186] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Idiopathic pulmonary fibrosis (IPF) was reported to be associated with increased risk of lung cancer as a result of the occurrence of atypical or dysplastic epithelial changes in fibrosis which progressed to invasive malignancy. In that situation, the cancer will develop in the area of major fibrosis. To investigate the direct relationship between fibrosis and cancer development, the real concordance rate of the two lesions in the chest computed tomography (CT) was analysed and compared to the histological types of lung cancer. The subjects included 63 patients with combined lung cancer and IPF (IPF-CA), 218 patients with lone IPF, and 2,660 patients with primary lung cancer. All patients were diagnosed at Asan Medical Center during the same period. The age, percentage of smokers, and the male sex were significantly higher in IPF-CA compared with lone IPF. The odds ratio of smoking was 2.71 compared to nonsmoking IPF controls. In IPF-CA, 56% of the cancer was located in the periphery of the lung and 52% in the upper lobe. The majority of the cancers (64%) were found in the nonfibrotic area at chest CT. The most frequent cell type was squamous cell carcinoma (35%), and there was no significant difference in the cancer cell type between IPF-CA and total lung cancer population. These findings suggest that in combined lung cancer and idiopathic pulmonary fibrosis patients, the features of the lung cancer are similar to the total lung cancer population.
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Hong JY, Lee HJ, Piedra PA, Choi EH, Park KH, Koh YY, Kim WS. Lower respiratory tract infections due to adenovirus in hospitalized Korean children: epidemiology, clinical features, and prognosis. Clin Infect Dis 2001; 32:1423-9. [PMID: 11317242 DOI: 10.1086/320146] [Citation(s) in RCA: 147] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2000] [Revised: 09/18/2000] [Indexed: 02/04/2023] Open
Abstract
On occasion, outbreaks of infection with adenovirus types 3, 7, and 21 cause severe lower respiratory tract infections (LRTIs) in children. From 1990 to 1998, all cases of LRTI due to adenovirus at the Seoul National University Children's Hospital, Seoul, Korea, were reviewed. Adenoviruses were recovered from nasal aspirate specimens of 87 (5.9%) of 1472 children with LRTI. The principal adenovirus serotypes were type 2 (13 [15%] of 87 strains), type 3 (13 [15%]), and type 7 (36 [41%]). Of the 87 infections, 62 (71%) occurred in children <2 years of age, and 81 (94%) occurred in children <5 years of age. Infections due to types 3 and 7 occurred during epidemics, whereas infections due to type 2 occurred sporadically. For patients who were infected with types 3 and 7, extrapulmonary abnormalities were more common and homogeneous consolidation and pleural effusion were frequently identified on radiographs. The mortality rate was 12% overall and 19% among patients who were infected with type 7. Residual sequelae were identified in 6 (50%) of 12 patients who were infected with type 3 and in 9 (25%) of 36 who were infected with type 7. The data confirm that adenovirus types 3 and 7 can cause epidemics of severe LRTI in young children. Epidemics of LRTIs caused by adenovirus types 3 and 7 in Korea have not been described in reports published elsewhere.
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Cho HH, Kim WS, Yu MS, Bae JC. Analysis of particle laden flow and heat transfer in cascade and rocket nozzle. Ann N Y Acad Sci 2001; 934:233-40. [PMID: 11460631 DOI: 10.1111/j.1749-6632.2001.tb05855.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
This paper presents results for the calculation of particle trajectories in a cascade and a rocket nozzle using a Lagrangian method. When the floating particles collide to the components, the component surface is damaged severely. The surface erosion rate is strongly dependent on a particle size, a particle impact angle and a surface material. For a compressor cascade, the particle impact rate increases proportionally with the flow inlet angle and the erosion rate on the pressure side surface of blade are related to the surface or coating materials. For a solid rocket nozzle, the particle free zone in the nozzle divergent section increases quickly with increasing particle size and the maximum heat transfer density occurs at the starting region of nozzle convergent section. The Al2O3 droplet breaks up around the nozzle throat due to the high velocity difference between the droplet and gas stream, resulting in the big change of particle free zone.
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Choi YH, Kim IO, Cheon JE, Kim WS, Yeon KM, Wang KC, Cho BK, Chi JG. Gangliocytoma of the spinal cord: a case report. Pediatr Radiol 2001; 31:377-80. [PMID: 11373931 DOI: 10.1007/s002470100445] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
We present a case of intramedullary spinal gangliocytoma in a 7-year-old girl who presented with scoliosis and progressive weakness of both legs. The tumour involved the whole spinal cord and medulla oblongata and was composed of inner cystic and outer solid components. On MRI, the solid portion of the lesion showed strong enhancement at the thoracolumbar level and mild enhancement at the cervical and medullary levels. Histological examination of the surgical specimen showed neoplastic ganglion cells arranged irregularly in benign normocellular glial background, which made a diagnosis of gangliocytoma.
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