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Kim AY, Cho KS, Song KS, Kim JH, Kim JG, Ha HK. Urinary calculi on computed radiography: comparison of observer performance with hard-copy versus soft-copy images on different viewer systems. AJR Am J Roentgenol 2001; 177:331-5. [PMID: 11461856 DOI: 10.2214/ajr.177.2.1770331] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE The purpose of this study was to compare observer performance for detecting urinary calculi using abdominal computed radiography with hard-copy versus soft-copy images and with a high-resolution video monitor versus a liquid-crystal-display (LCD) monitor. MATERIALS AND METHODS We compared observer performance for detecting urinary calculi using three sets of radiographs-hard-copy images, soft-copy images displayed on a LCD monitor (1280 x 1024 bits), and soft-copy images displayed on a high-resolution video monitor using receiver operating characteristic curve analysis with a continuous rating scale. Computed radiography was archived with a 2140 x 1760 pixel resolution and a 10-bit depth. The selected data set included 62 images: 27 images showing proven urinary calculi smaller than 6 mm and three in number, and 35 images containing no proven abnormalities. Eleven radiologists (three genitourinary radiologists and eight general radiologists) participated in the study. Interpretations of three sets of randomly distributed radiographs were performed individually in three separate sessions at 1-week intervals. RESULTS No statistically significant differences were found in the area under the receiver operating characteristic curve for detecting urinary calculi or in the interpreting times between soft-copy and hard-copy images; the mean areas under the receiver operating characteristic curve of hard-copy images, soft-copy images displayed on an LCD monitor, and soft-copy images displayed on a high-resolution video monitor were 0.579, 0.610, and 0.732, respectively. However, soft-copy images showed relatively improved diagnostic accuracy among less experienced radiologists (p < 0.05). CONCLUSION For detecting urinary calculi, soft-copy images offered a diagnostic accuracy similar to or slightly more accurate than that of hard-copy images obtained in a laser-printed film-based environment. The diagnostic performance with soft-copy images viewed on an LCD monitor was comparable to that of soft-copy images viewed on a high-resolution video monitor.
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Lee SH, Kim WH, Kim HK, Woo KM, Nam HS, Kim HS, Kim JG, Cho MH. Altered expression of the fragile histidine triad gene in primary gastric adenocarcinomas. Biochem Biophys Res Commun 2001; 284:850-5. [PMID: 11396980 DOI: 10.1006/bbrc.2001.5038] [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: 11/22/2022]
Abstract
Genomic alterations and abnormal expression of the fragile histidine triad (FHIT) gene in gastric carcinomas were examined to determine whether the FHIT gene is actually a frequent target for alteration during gastric carcinogenesis. To correlate DNA and RNA lesions of the FHIT gene with the effect on FHIT protein expression, we have investigated the FHIT gene for loss of heterozygosity (LOH), aberrant transcripts, point mutations, and protein expression in 35 gastric adenocarcinomas. Allelic loss at D3S1300 was detected in 7 of 33 (21%) informative cases. Aberrant transcripts, with deletions and/or insertions, were observed in 20 of 35 (57.1%) cases and resulted from alternative splicing through exon skipping and/or insertion of the FHIT intron 5 sequence or activation of the cryptic splice site. Point mutations were not found in the FHIT coding region but detected in noncoding exon 2, 3, 4, or 5 of eight aberrant transcripts. Significant reduction of FHIT protein expression was observed in 22 of 35 (62.9%) cases. Aberrant FHIT transcription was shown to be associated with loss of FHIT protein expression. However, aberrant FHIT transcripts themselves were not associated with any clinicopathological parameters, such as age, sex, tumor site, or clinical stage. Moreover, there was no association between the presence of LOH at D3S1300 and the expression of aberrant FHIT transcripts. Nevertheless, high frequency of aberrant FHIT transcripts, significant rate of LOH at D3S1300, and altered expression of the FHIT protein indicate that alterations of the FHIT gene can play an important role in gastric carcinogenesis.
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Lee SE, Lee BH, Choi WS, Park BS, Kim JG, Campbell BC. Fumigant toxicity of volatile natural products from Korean spices and medicinal plants towards the rice weevil, Sitophilus oryzae (L). PEST MANAGEMENT SCIENCE 2001; 57:548-553. [PMID: 11407032 DOI: 10.1002/ps.322] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The fumigant toxicity of various volatile constituents of essential oils extracted from sixteen Korean spices and medicinal plants towards the rice weevil, Sitophilus oryzae L (Coleoptera: Curculionidae), was determined. The most potent toxicity was found in the essential oil from Mentha arvensis L. var piperascens (LC50 = 45.5 microliters litre-1 air). GC-MS analysis of essential oil from M arvensis showed it to be rich in menthol (63.2%), menthone (13.1%) and limonene (1.5%), followed in abundance by beta-pinene (0.7%), alpha-pinene (0.6%) and linalool (0.2%). Treatment of S oryzae with each of these terpenes showed menthone to be most active (LC50 = 12.7 microliters litre-1 air) followed by linalool (LC50 = 39.2 microliters litre-1 air) and alpha-pinene (LC50 = 54.9 microliters litre-1 air). Studies on inhibition of acetylcholinesterase activity of S oryzae showed menthone to have a nine-fold lower inhibitory effect than menthol, despite menthone being 8.1-fold more toxic than menthol to the rice weevil. Different modes of toxicity of these monoterpenes towards S oryzae are discussed.
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Lee JE, Park JC, Kim JG, Suh H. Preparation of collagen modified hyaluronan microparticles as antibiotics carrier. Yonsei Med J 2001; 42:291-8. [PMID: 11456394 DOI: 10.3349/ymj.2001.42.3.291] [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: 11/27/2022] Open
Abstract
Hyaluronan (HA), a natural glycoaminoglycan featuring an extracellular matrix, has been suggested as an effective biocompatible material. In this study, the effectiveness of HA microparticles as a carrier system for antibiotics was evaluated, and their physicochemical characteristics were determined. Microparticles were fabricated by the gelation of sulfadiazine (SD) loaded HA solution with calcium chloride through either a granulation (GR-microparticles) or encapsulation (EN-microparticles) process, and atelocollagen was incorporated into the microparticles as an additive in order to improve their physical properties. The characteristics of the microparticles were examined by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and swelling test. In vitro release experiments were performed for 7 days and the released amount of SD was determined using high-performance liquid chromatography (HPLC). Microscopic observations revealed that the collagen incorporated HA particles had a more compact surface than the HA particles. DSC analysis determined a loss of SD crystallinity in the particles. Calcium chloride retarded the swelling of particles, whereas the loaded drug contents did not affect this property. Both GR-and EN-microparticles sustained SD release with initial bursting effect. SD release from EN-microparticles was faster than from GR-microparticles. In addition, the release rate was dependent on the SD content in the microparticles. These results suggest that collagen modified HA microparticles have a potential as a release rate controlling material for crystalline drugs such as SD.
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Kang HJ, Kim SC, Kim YJ, Kim CW, Kim JG, Ahn HS, Park SI, Jung MH, Choi BC, Kimm K. Short-term phytohaemagglutinin-activated mononuclear cells induce endothelial progenitor cells from cord blood CD34+ cells. Br J Haematol 2001; 113:962-9. [PMID: 11442490 DOI: 10.1046/j.1365-2141.2001.02694.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Endothelial progenitor cells (EPCs) were recently demonstrated to exist in human cord blood. Phytohaemagglutinin (PHA), a potent mitogen for mononuclear cells was used to induce EPCs from unsorted cord blood mononuclear cells (CBMCs). Adherent cells in clusters appeared approximately 24 h after CBMCs were cultured in plain Roswell Park Memorial Institute media containing 10% fetal bovine serum (culture media) and PHA. Adherent cells were further propagated for 1 week in plain culture media. Flow cytometry and Di-I staining analyses showed that CD45-, CD34+, Flk-1+, CD31+ or VE-cadherin+ EPCs were induced and that they were mainly from the CD34+ cell compartment. When enriched CD34+ cells alone were stimulated with culture supernatant of the PHA-activated CBMCs, they neither proliferated readily nor induced EPCs. Because EPCs first appeared within the clustering cells that expressed high levels of fibronectin and vascular endothelial growth factor (VEGF), our data suggest that both cell-cell/cell-matrix interaction and the local VEGF action are important in the induction of EPCs. Thus, we demonstrate for the first time that EPCs are induced from human cord blood stem cell populations that interact with neighbouring PHA-activated CBMCs. This finding may have a significant implication in inflammatory cell-mediated vasculogenesis and angiogenesis in vivo.
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Unal R, Kim JG, Yousef AE. Inactivation of Escherichia coli O1 57:H7, Listeria monocytogenes, and Lactobacillus leichmannii by combinations of ozone and pulsed electric field. J Food Prot 2001; 64:777-82. [PMID: 11403125 DOI: 10.4315/0362-028x-64.6.777] [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: 11/11/2022]
Abstract
Pulsed electric field (PEF) and ozone technologies are nonthermal processing methods with potential applications in the food industry. This research was performed to explore the potential synergy between ozone and PEF treatments against selected foodborne bacteria. Cells of Lactobacillus leichmannii ATCC 4797, Escherichia coli O157:H7 ATCC 35150, and Listeria monocytogenes Scott A were suspended in 0.1% NaCl and treated with ozone, PEF, and ozone plus PEE Cells were treated with 0.25 to 1.00 microg of ozone per ml of cell suspension, PEF at 10 to 30 kV/cm, and selected combinations of ozone and PEF. Synergy between ozone and PEF varied with the treatment level and the bacterium treated. L. leichmannii treated with PEF (20 kV/cm) after exposure to 0.75 and 1.00 microg/ml of ozone was inactivated by 7.1 and 7.2 log10 CFU/ml, respectively; however, ozone at 0.75 and 1.00 microg/ml and PEF at 20 kV/cm inactivated 2.2, 3.6, and 1.3 log10 CFU/ml, respectively. Similarly, ozone at 0.5 and 0.75 microg/ml inactivated 0.5 and 1.8 log10 CFU/ml of E. coli, PEF at 15 kV/cm inactivated 1.8 log10 CFU/ml, and ozone at 0.5 and 0.75 microg/ml followed by PEF (15 kV/cm) inactivated 2.9 and 3.6 log10 CFU/ml, respectively. Populations of L. monocytogenes decreased 0.1, 0.5, 3.0, 3.9, and 0.8 log10 CFU/ml when treated with 0.25, 0.5, 0.75, and 1.0 microg/ml of ozone and PEF (15 kV/cm), respectively; however, when the bacterium was treated with 15 kV/cm, after exposure to 0.25, 0.5, and 0.75 microg/ml of ozone, 1.7, 2.0, and 3.9 log10 CFU/ml were killed, respectively. In conclusion, exposure of L. leichmannii, E. coli, and L. monocytogenes to ozone followed by the PEF treatment showed a synergistic bactericidal effect. This synergy was most apparent with mild doses of ozone against L. leichmannii.
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Yoon HG, Yoon SH, Son WY, Kim JG, Im KS, Lim JH. Alternative embryo transfer on day 3 or day 5 for reducing the risk of multiple gestations. J Assist Reprod Genet 2001; 18:262-7. [PMID: 11464577 PMCID: PMC3455334 DOI: 10.1023/a:1016651016502] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
PURPOSE This study was carried out to reduce the possibility of high-order multiple gestations and the failure of embryo transfer by determining their replacement date based on the number and quality of 2-day embryos. METHODS All zygotes were cocultured with cumulus cells in 10 microliters of YS medium containing 10% human follicular fluid (hFF) for 48 or 96 hr. In period I, all embryos were transferred on day 3 (1032 cycles). In period II, the embryos were transferred on either day 3 or day 5 by determining their replacement date based on the number and quality of 2-day embryos: there were 2701 patients in whom embryos were replaced on day 3 (in the case that the number of zygotes was less than eight and the number of good-quality embryos was less than three) and 1952 patients less than 40 years old in whom embryos were replaced on day 5 (in the case that the number of zygotes was eight or more and/or the number of good-quality embryos was three or more). On the other hand, patients who were 40 years old or more were alloted to day 3 transfer cycles, regardless of the number and quality of the 2-day embryos, due to the possibility of their not producing blastocyst-stage embryos in vitro. RESULTS The number of embryos transferred in period II was 2.9 +/- 0.6, while that in period I was 3.7 +/- 0.5. The multiple pregnancy rate was significantly decreased in period II (30.7%) compared to that (49.6%) in period I, while the pregnancy and implantation rates in period II (36.1 and 16.4%, respectively) were not lower than those (34.9 and 16.1%, respectively) in period I. The rate of triplet or more gestations was significantly minimized in period II (2.3%) compared to that in period I (26.5%). CONCLUSIONS We propose that determination of the date on which embryos should be transferred based on the number and quality of embryos on day 2 may help to maintain an acceptable pregnancy rate, while minimizing embryo transfer failure and high-order multiple gestations.
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Park KU, Kim SH, Suh C, Kim S, Lee SJ, Park JS, Cho HJ, Kim KW, Lee K, Kim HJ, Park J, Joo Min Y, Kim JG, Kim T, Lee JH, Kim SB, Kim SW, Lee KH, Lee JS, Kim WK, Park CJ, Chi HS. Correlation of hematopoietic progenitor cell count determined by the SE-automated hematology analyzer with CD34(+) cell count by flow cytometry in leukapheresis products. Am J Hematol 2001; 67:42-7. [PMID: 11279656 DOI: 10.1002/ajh.1074] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The yield of stem cell collection after mobilization is crucial for autologous peripheral blood stem cell (PBSC) transplantation. Quantitative determinations of CD34(+) cells using flow cytometry or stem cell culture have been used, but these methods require much time, technical experience, and expensive reagents. The automated hematology analyzer (Sysmex SE-9000trade mark, TOA, Japan) equipped with the Immature Information (IMI) channel for immature myeloid cells can detect IMI(+) cells within 90 sec. Detection is made possible by the combination of a special reagent system and direct current/radiofrequency biosensors. We studied the relation of IMI(+) cells and variable cell counts with CD34(+) cell yield in autologous stem cell harvest. In a series of 32 patients (median age, 44 years; M:F = 11:21), 184 leukaphereses were performed after mobilization regimens with chemotherapy and G-CSF or G-CSF alone. Full blood cell counts were enumerated on peripheral blood (PB) samples taken prior to each leukapheresis. Mononuclear cell (MNC) and IMI(+) cell counts by automated hematology analyzer and flow cytometry based CD34(+) cell yield were measured on the harvested product. The relationship among PB white blood cells (WBC), PB monocytes, IMI(+) cells, MNC, and CD34(+) cell yield in a single leukapheresis was estimated by Pearson correlation analysis. PB WBC count showed no correlation with CD34(+) cell yield in a single leukapheresis (r = 0.02, P = 0.81). PB monocyte count showed a weak correlation (r = 0.21, P = 0.01) and MNC in harvest also showed a weak correlation (r = 0.36, P = 0.0001) with CD34(+) cell yield. In contrast, CD34(+) cell yield correlated well with IMI(+) cell count (r = 0.68, P = 0.0001), and data could be fitted by a linear regression equation, y = 0.330 + 0.974x. IMI(+) cell assay by the automated hematology analyzer correlated well with the CD34(+) cell yield in a mobilized autologous stem cell harvest. The IMI(+) cell count might be used as a simple and efficient indicator of blood stem cell mobilization and collection.
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Kim JG, Vallet JL, Christenson RK. Characterization of uterine epidermal growth factor during early pregnancy in pigs. Domest Anim Endocrinol 2001; 20:253-65. [PMID: 11518619 DOI: 10.1016/s0739-7240(01)00097-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Genomic research has identified a quantitative trait locus for uterine capacity, a component trait contributing to litter size, on porcine chromosome 8. The epidermal growth factor (EGF) gene, on porcine chromosome 8, may influence uterine capacity because of its growth-promoting activities. Using reverse transcription-polymerase chain reaction (PCR) and iterative screening of a porcine reproductive tissue cDNA library, 4932 bp cDNA sequence coding for porcine EGF precursor was obtained. The predicted protein sequence of the EGF precursor contained 1214 amino acids, similar to human EGF precursor (1207 amino acids, 81% identity). Curiously, the sequence of the mature peptide was less homologous between species than other regions of EGF precursor. The presence of conserved regions outside the mature peptide may suggest that these regions are functionally important. Expression of EGF mRNA in the endometrium of White crossbred gilts (n = 3 to 5 each) was determined by Northern blotting using 20 microg of total RNA from endometrium of D 10, 13, and 15 cyclic, and D 10, 13, 15, 20, 30, and 40 of pregnant gilts. A 3342 bp probe from EGF precursor was used. The bands corresponding to EGF mRNA were quantified by densitometry and results were analyzed by ANOVA. EGF mRNA expression decreased significantly from D 13 to 15 of the cycle and pregnancy (P = 0.04), and from D 30 to 40 of pregnancy (P = 0.01). These findings show that EGF mRNA expression is temporally regulated during the cycle and early pregnancy, and this pattern of gene expression may be important during early conceptus development.
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Kim JG, Lee JY. Changes in profiles of circulating insulin-like growth factor components during hormone replacement therapy according to the responsiveness to therapy in postmenopausal women. Am J Obstet Gynecol 2001; 184:1139-44. [PMID: 11349179 DOI: 10.1067/mob.2001.112588] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVES Objectives of this study were (1) to evaluate the changes in the profiles of circulating insulin-like growth factor and of insulin-like growth factor-binding proteins during hormone replacement therapy and their relation with responsiveness to hormone replacement therapy and (2) to investigate the relationship between the changes in these insulin-like growth factor components and the annual changes in bone mineral density in postmenopausal women. STUDY DESIGN Insulin-like growth factor and insulin-like growth factor-binding proteins were measured by immunoradiometric assay and Western ligand blotting in sera from 39 postmenopausal women treated with sequential hormone replacement therapy for 1 year. Bone mineral density at the lumbar spine and the proximal portion of the femur was determined by dual-energy x-ray absorptiometry. RESULTS No significant change in the serum levels of insulin-like growth factor II and insulin-like growth factor-binding protein was noted during hormone replacement therapy in either the responders to therapy or the nonresponders (women with >3% bone loss per year), but serum levels of insulin-like growth factor I and proportions of insulin-like growth factor-binding proteins 1, 2, and 4 decreased during hormone replacement therapy only in the former group. Changes in insulin-like growth factor components during hormone replacement therapy did not correlate with annual bone mineral density changes. CONCLUSION Profiles of circulating insulin-like growth factor I and insulin-like growth factor-binding proteins might be involved in responsiveness to hormone replacement therapy, but changes in these components during hormone replacement therapy do not predict annual changes in bone mineral density.
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Berndt JA, Kim JG, Tosic M, Kim C, Hudson LD. The transcriptional regulator Yin Yang 1 activates the myelin PLP gene. J Neurochem 2001; 77:935-42. [PMID: 11331422 DOI: 10.1046/j.1471-4159.2001.00307.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Inauguration of the myelin program in developing oligodendrocytes requires the activation of those genes that encode the myelin proteins and the enzymes responsible for the synthesis and degradation of myelin lipids. An activator of the most abundantly expressed myelin protein, proteolipid protein (PLP), has been identified in a yeast one-hybrid system. The ubiquitously expressed zinc finger protein Yin Yang 1 (YY1) recognizes the myelin PLP promoter in vitro and in vivo. When overexpressed in an oligodendrocyte cell line, YY1 enhances transcription of the PLP promoter. A truncated version of YY1 that includes only the four zinc finger domains has little effect. The binding site for YY1 in the PLP promoter (site 3) fits the YY1 consensus site and DNA-protein complexes containing site 3 can be supershifted with an antibody directed against YY1 protein. Moreover, oligonucleotides with a mutated version of the PLP promoter site 3 are unable to bind to nuclear proteins or to compete for binding in a gel shift system. Finally, mutation of this site greatly reduces the activity of a 1-kb PLP promoter region in transfected glial cells. Our results suggest that PLP is a target gene for the transcriptional regulator YY1. This versatile transcription factor and nuclear matrix protein may boost transcription of the PLP gene to meet the demands of actively myelinating oligodendrocytes.
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Kim JG, Lim KS, Kim EK, Choi YM, Lee JY. Association of vitamin D receptor and estrogen receptor gene polymorphisms with bone mass in postmenopausal Korean women. Menopause 2001; 8:222-8. [PMID: 11355046 DOI: 10.1097/00042192-200105000-00013] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To examine the relationship between vitamin D receptor (VDR) and estrogen receptor (ER) gene polymorphism and bone mineral density (BMD). DESIGN Polymorphisms at the VDR FokI and ER PvuII and XbaI gene sites, serum bone-specific alkaline phosphatase, urinary N-telopeptide of type I collagen, and BMD at the lumbar spine and proximal femur were analyzed in 229 postmenopausal Korean women. RESULTS The distribution of ER PvuII and XbaI and VDR FokI restriction fragment length polymorphisms was as follows: pp 39.3%, Pp 46.3%, PP 14.4%, xx 34.1%, Xx 61.1%, XX 4.8%. ff 17.0%, Ff 43.7%, and FF 39.3%, respectively (upper-case letters signify the absence, and lower-case letters signify the presence of the restriction site). After adjusting for potential confounding factors such as age, body mass index, and menopause duration, ER PvuII was independently associated with BMD at the lumbar spine and XbaI polymorphism BMD at the femoral neck. The lumbar spine BMD in the pp genotype was 7.5% lower than in the PP genotype, and the femoral neck BMD was 4.8% lower in the Xx genotype than in the xx genotype. By itself, the VDR FokI polymorphism was not related to BMD, but by combining the FokI genotype (FF) with ER genotypes, such as ppxx and the PpXx, the difference in the BMD at the Ward's triangle became significant. There were no significant differences in the levels of biochemical markers between the genotypes of three polymorphisms. CONCLUSION ER polymorphisms, singly and in relation to VDR FokI polymorphism, influence bone mass in Korean women.
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Yang CH, Murti A, Pfeffer SR, Kim JG, Donner DB, Pfeffer LM. Interferon alpha /beta promotes cell survival by activating nuclear factor kappa B through phosphatidylinositol 3-kinase and Akt. J Biol Chem 2001; 276:13756-61. [PMID: 11278812 DOI: 10.1074/jbc.m011006200] [Citation(s) in RCA: 159] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Interferons (IFNs) play critical roles in host defense by modulating gene expression via activation of signal transducer and activator of transcription (STAT) factors. IFN-alpha/beta also activates another transcription factor, nuclear factor kappaB (NF-kappaB), which protects cells against apoptotic stimuli. NF-kappaB activation requires the IFN-dependent association of STAT3 with the IFNAR1 chain of the IFN receptor. IFN-dependent NF-kappaB activation involves the sequential activation of a serine kinase cascade involving phosphatidylinositol 3-kinase (PI-3K) and Akt. Whereas constitutively active PI-3K and Akt induce NF-kappaB activation, Ly294002 (a PI-3K inhibitor), dominant-negative PI-3K, and kinase-dead Akt block IFN-dependent NF-kappaB activation. Moreover, dominant-negative PI-3K blocks IFN-promoted degradation of kappaBox alpha. Ly294002, a dominant-negative PI-3K construct, and kinase-dead Akt block IFN-promoted cell survival, enhancing apoptotic cell death. Therefore, STAT3, PI-3K, and Akt are components of an IFN signaling pathway that promotes cell survival through NF-kappaB activation.
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Lim TH, Kwon H, Jeon CH, Kim JG, Sokolowski M, Natarajan R, An HS, Andersson GB. Effect of endplate conditions and bone mineral density on the compressive strength of the graft-endplate interface in anterior cervical spine fusion. Spine (Phila Pa 1976) 2001; 26:951-6. [PMID: 11317120 DOI: 10.1097/00007632-200104150-00021] [Citation(s) in RCA: 132] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN Destructive compression tests and finite element analyses were conducted to investigate the biomechanical strength at the graft-endplate interface in anterior cervical fusion. OBJECTIVES To investigate the effect of endplate thickness, endplate holes, and bone mineral density of the vertebral body on the biomechanical strength of the endplate-graft interface in an anterior interbody fusion of the cervical spine. SUMMARY OF BACKGROUND Subsidence of the graft into the vertebral body is a well-known complication in anterior cervical fusion. However, there is no information in the literature regarding the compressive strength of the graft-endplate interface in relation to the endplate thickness, holes in the endplate, and bone mineral density of the vertebral body. METHODS Biomechanical destructive compression tests and finite element analyses were performed in this study. Cervical vertebral bodies (C3-C7) isolated from seven cadaveric cervical spines (age at death 69-86 years, mean 79 years) were used for compression tests. Bone mineral density of each vertebral body was measured using a dual energy radiograph absorptiometry unit. Endplate thickness was measured using three coronal computed tomography images of the middle portion of the vertebral body obtained using a computer-assisted imaging analysis. Then each vertebral body was cut into halves through the horizontal plane. A total of 54 specimens, consisting of one endplate and half of the vertebral body, were obtained after excluding eight vertebrae with gross pathology on plain radiograph. Specimens were assigned to one of three groups with different endplate conditions (Group I, intact; Group II, partial removal; and Group III, complete removal) so that group mean bone mineral density became similar. Each endplate was slowly compressed until failure using an 8-mm-diameter metal indenter, and the load to failure was determined as a maximum force on a recorded force-displacement curve. The effect on the strength of the graft-endplate interface of various hole patterns in the endplate was studied using a finite element technique. The simulatedhole patterns included the following: one large central hole, two lateral holes, two holes in the anterior and posterior portion of the endplate, and four holes evenly distributed from the center of the endplate. Stress distribution in the endplate was predicted in response to an axial compressive force of 110 N, and the elements with von Mises stress greater than 4.0 MPa were determined as failed. RESULTS The endplate thickness and bone mineral density were similar at all cervical levels, and the superior and inferior endplates had similar thickness at all cervical levels. There was no significant association between bone mineral density and endplate thickness. Load to failure was found to have a significant association with bone mineral density but not with endplate thickness. However, load to failure tends to decrease with incremental removal of the endplate, and load to failure of the specimens with an intact endplate was significantly greater than that of the specimens with no endplate. Finite element model predictions showed significant influence of the hole pattern on the fraction of the upper endplate exposed to fracture stress. A large hole was predicted to be more effective than the other patterns at distributing a compressive load across the remaining area and thus minimizing the potential fracture area. CONCLUSION Results of this study suggest that it is important to preserve the endplate as much as possible to prevent graft subsidence into the vertebral body, particularly in patients with poor bone quality. It is preferable to make one central hole rather than multiple smaller holes in the endplate for vascularity of the bone graft because it reduces the surface area exposed to fracture stresses.
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Lee JE, Park JC, Hwang YS, Kim JK, Kim JG, Sub H. Characterization of UV-irradiated dense/porous collagen membranes: morphology, enzymatic degradation, and mechanical properties. Yonsei Med J 2001; 42:172-9. [PMID: 11371103 DOI: 10.3349/ymj.2001.42.2.172] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Collagen-based membranous materials of various shapes (gel, film, sponge) are known to be the most promising materials in terms of facilitating the regeneration of dermal defects. In this study, dense and porous collagen membranes were fabricated using air-drying and freeze-drying processes, respectively, and the effect of ultraviolet (UV) radiation on the degree of membrane crosslinking was evaluated by in vitro biodegradation and mechanical testing. A non-irradiated membrane group was used as the negative control and a glutaraldehyde (GA) treated group as the positive control. Scanning electron microscopy showed that, as the freezing temperature decreased to -196 degrees C, the resultant mean pore sizes also decreased; optimal pore size was obtained at a freezing temperature of -70 degrees C. In vitro biodegradation and mechanical testing demonstrated that GA treatment or 4 hours of exposure to UV radiation significantly increased both resistance to collagenase and mechanical strength versus the untreated controls, regardless of the collagen membrane type (dense or porous). Our results suggest that UV treatment is a useful tool for the fabrication of collagen membranes designed to be used as dermal dressings.
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Kim JJ, Reddy R, Lee M, Kim JG, El-Zaatari FA, Osato MS, Graham DY, Kwon DH. Analysis of metronidazole, clarithromycin and tetracycline resistance of Helicobacter pylori isolates from Korea. J Antimicrob Chemother 2001; 47:459-61. [PMID: 11266421 DOI: 10.1093/jac/47.4.459] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Antibiotic resistance in Helicobacter pylori varies according to geographical region. We studied the primary resistance rates among 652 H. pylori isolated from Korea in relation to collection date, disease presentation, age and gender. Resistance rates were 40.6% (metronidazole), 5.9% (clarithromycin), 5.3% (tetracycline), 0% (amoxycillin), 1.5% (furazolidone) and 1.5% (nitrofurantoin). Resistance to metronidazole and clarithromycin increased from 1994 to 1999 (from 33.3 to 47.7% and 4.8 to 7.7%, respectively), but the differences only reached significance when rates of metronidazole resistance in women were compared with those in men (48.6 versus 36.9%).
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Standish LJ, Greene KB, Bain S, Reeves C, Sanders F, Wines RC, Turet P, Kim JG, Calabrese C. Alternative medicine use in HIV-positive men and women: demographics, utilization patterns and health status. AIDS Care 2001; 13:197-208. [PMID: 11304425 DOI: 10.1080/095401201300059759] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Between 1995 and 1997, 1,675 HIV-positive men and women using complementary and alternative medicine (CAM) were enrolled into the Bastyr University AIDS Research Center's Alternative Medicine Care Outcomes in AIDS (AMCOA) study. Funded by the National Institutes of Health (NIH) Office of Alternative Medicine (OAM) and National Institute of Allergy and Infectious Diseases (NIAID), the AMCOA study collected information on participant demographics, health status and use of conventional and CAM therapies. Participants from 46 states completed a baseline questionnaire, while additional clinical information (such as CD4 count and HIV-RNA viral load) was obtained from laboratory records. AMCOA participants reported using more than 1,600 different types of CAM therapies (1,210 CAM substances, 282 CAM therapeutic activities and 119 CAM provider types) for treating HIV/AIDS. Approximately two-thirds (63% n = 1,054) of the AMCOA cohort reported using antiretroviral drug therapy (ART) during the six-months previous to completing the baseline questionnaire, while 37% (n = 621) indicated they were not using ART. Of those not using ART, 104 subjects reported never having used any conventional medications for their HIV and 12 subjects used only non-prescription diarrhoea medications. The most frequently reported CAM substances were vitamin C (63%), multiple vitamin and mineral supplements (54%), vitamin E (53%) and garlic (53%). CAM provider types most commonly consulted by the AMCOA cohort were massage therapists (49%), acupuncturists (45%), nutritionists (37%) and psychotherapists (35%). CAM activities most commonly used were aerobic exercise (63%), prayer (58%), massage (53%) and meditation (46%). The choice of CAM therapies among the AMCOA cohort does not appear to be solely based on scientific evidence of efficacy of individual therapies. The majority of AMCOA subjects could be characterized as using integrated medicine, since an overwhelming proportion of the cohort consult with both conventional and CAM providers and use both conventional and CAM medications, yet few subjects reported that their conventional and CAM providers work as a team. These data and this cohort set the stage for conducting studies of health status changes associated with specific CAM therapies.
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Gutierrez O, Kim JG, Akamatsu T, Gürer IE, Simjee AE, Graham DY. Geographic differences in the distribution of intestinal metaplasia in duodenal ulcer patients. Am J Gastroenterol 2001; 96:666-72. [PMID: 11280531 DOI: 10.1111/j.1572-0241.2001.03601.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE A strong correlation exists between atrophic gastritis and the intestinal type of gastric carcinoma. Duodenal ulcer disease characteristically has an antral predominant gastritis and a lower risk for gastric cancer. The aim of this study was to investigate the extent and distribution of intestinal metaplasia in duodenal ulcer in countries differing in gastric cancer incidence. METHODS Topographically mapped gastric biopsy specimens (median 11) were obtained from patients with duodenal ulcer in four countries (Korea, Colombia, USA, and South Africa). Sections were stained with a triple stain and evaluated for Helicobacter pylori (H. pylori), active inflammation, and intestinal metaplasia. RESULTS One hundred and sixty-five patients with duodenal ulcer were examined (29 from Korea, 52 from Colombia, 62 from the USA, and 22 from South Africa). The percentage of biopsies with intestinal metaplasia was significantly greater in Korean patients (86%) compared with that in other countries (50%) (p = 0.0004). Intestinal metaplasia was most prevalent in the antrum lesser curve and greater curve, and the body lesser curve. Intestinal metaplasia was present in the gastric corpus of 38% of duodenal ulcer patients from Korea compared with an average of 10% elsewhere (p = 0.018). No differences were observed in the density or distribution of H. pylori infection or in the degree of active gastritis between countries. CONCLUSIONS Although antral predominant gastritis is the prevalent pattern of gastritis in duodenal ulcer, intestinal metaplasia in the gastric corpus may be found with geographic differences. These findings suggest that duodenal ulcer and gastric cancer are not mutually exclusive diseases but are rather ends of the spectrum of H. pylori infection.
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Park SM, Park J, Kim JG, Yoo BC. Relevance of vacA genotypes of Helicobacter pylori to cagA status and its clinical outcome. Korean J Intern Med 2001; 16:8-13. [PMID: 11417307 PMCID: PMC4531701 DOI: 10.3904/kjim.2001.16.1.8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Determination of vacA mosaicism may be important because specific Helicobacter pylori vacA genotype can be used to predict different clinical outcome. The aim of this study was to assess the relationship of vacA genotypes of Helicobacter pylori to cagA status and its development of peptic ulcer diseases in Korean patients. METHODS Gastric biopsy specimens were obtained from 53 patients with gastric ulcer(GU), 57 with duodenal ulcer (DU) and 26 with chronic gastritis(CG) patients; all patients were infected with Helicobacter pylori. Bacterial mRNAs in the gastric mucosa were amplified by RT-PCR, using synthetic oligonucleotide primers specific for the vacA and the cagA gene. Patients with vacA s1 subtype were further examined to determine whether they had s1a or s1b subtype. RESULTS There was no correlation in frequency of vacA s1 and/or s1a genotype between CG and either GU or DU, as the vacA s1 and s1a/m1 were present in the majority of strains independent of clinical status(s1; 100.0% versus 94.3% or 93.0% and s1a/m1; 76.9% versus 62.3% or 64.9%, respectively). Likewise, there was no difference in the prevalence of the cagA gene between CG and either GU or DU patients (92.3% versus 90.6% or 98.2%, respectively). In addition, the cagA-negative status did not predict the presence of vacA s2 genotype. CONCLUSION These results strongly suggest that either cagA or vacA s1 and/or s1a is not proved to be a useful marker to distinguish disease-specific Helicobacter pylori strains for the development of peptic ulcer diseases in Korean patients.
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Sim W, Lee JY, Kim JS, Kim JG, Suh IH. 6,7-Bis(bromomethyl)-2,11,18,21,24-pentaoxatetracyclo. Acta Crystallogr C 2001; 57:293-4. [PMID: 11250583 DOI: 10.1107/s0108270100018473] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2000] [Accepted: 11/23/2000] [Indexed: 11/11/2022] Open
Abstract
The 17-crown-5 unit, C(26)H(26)Br(2)O(5), consisting of a 1,2-bis(bromomethyl) group, three benzo groups and diethylene glycol, was prepared from the reaction of 1,2,4,5-tetrakis(bromomethyl)benzene and bis-phenol in the presence of sodium hydride as a base. This molecule seems to offer an internal cavity for the formation of a host--guest complex.
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Choi YM, Jun JK, Choe J, Hwang D, Park SH, Ku SY, Kang D, Kim JG, Moon SY, Lee JY. Association of the vitamin D receptor start codon polymorphism (FokI) with bone mineral density in postmenopausal Korean women. J Hum Genet 2001; 45:280-3. [PMID: 11043509 DOI: 10.1007/s100380070016] [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: 11/30/2022]
Abstract
We undertook this study in order to examine the association between bone mineral density (BMD) and a polymorphism at the first of two potential translation initiation codons in the vitamin D receptor (VDR) gene. This polymorphism was detected by restriction fragment length polymorphism analysis, using polymerase chain reaction (PCR) and the restriction endonuclease FokI. The f allele indicates the presence of the FokI site, and the F allele its absence. The FokI genotype was determined in 174 postmenopausal Korean women, aged 43-71 years. The distribution of FokI genotypes in Koreans was found not to differ significantly from those found in Caucasians and Japanese, although it does differ significantly from that found in the black American population. We observed a significant association between the FokI polymorphism and lumbar BMD; P = 0.048, analysis of covariance [ANCOVA], but no association with femoral neck BMD (P = 0.505, ANCOVA). Those with the ff genotype had a 13.3% lower BMD in the lumbar spine than the FF subjects. In addition, a significantly higher prevalence of the ff genotype was observed in osteoporotic compared with osteopenic or normal women (P = 0.036, chi2 test). These data suggest that the ff genotype of the VDR gene correlates with decreased BMD in the lumbar spine in postmenopausal Korean women.
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Yin F, Kim JG, Haughton C, Brown SL, Ajlouni M, Stronati M, Pamukov N, Kim JH. Extracranial radiosurgery: immobilizing liver motion in dogs using high-frequency jet ventilation and total intravenous anesthesia. Int J Radiat Oncol Biol Phys 2001; 49:211-6. [PMID: 11163517 DOI: 10.1016/s0360-3016(00)01370-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
PURPOSE Extracranial radiosurgery requires control of organ motion. The purpose of this study is to quantitatively determine the extent of liver motion in anesthetized dogs with continuous i.v. propofol infusion with or without muscle relaxants and high-frequency jet ventilation. METHODS AND MATERIALS Five dogs were used in the experiment. Each dog was restrained while anesthetized in the supine position using an alpha cradle. Surgical metal clips were implanted around the liver periphery so that its motion could be visualized using a fluoroscopic imaging device in a conventional simulator. Initially, two orthogonal simulation films were taken to correlate locations of implanted clips. Two orthogonal views of fluoroscopic images for each anesthetized dog were recorded on a magnetic tape and analyzed from the post-imaging data. Liver motion was documented under the following three conditions: 1) ventilated with a conventional mechanical ventilator, 2) ventilated with a high-frequency jet ventilator, and 3) ventilated with a high-frequency jet ventilator and total muscle paralysis (with vecuronium injection). The maximum liver motion for each dog was analyzed in three orthogonal directions: the inferior-to-superior direction, the anterior-to-posterior direction, and the right-to-left direction. RESULTS When the anesthetized dogs were ventilated with a conventional mechanical ventilator, the average liver motions were 1.2 cm in the inferior-to-superior direction, 0.4 cm in the anterior-to-posterior direction, and 0.2 cm in the right-to-left direction, respectively. After the introduction of high-frequency jet ventilation, the average liver motions were reduced to 0.2 cm in the inferior-to-superior direction, 0.2 cm in the anterior-to-posterior direction, and 0.1 cm in the right-to-left direction. The maximum liver motion was dependent on ventilator settings. There was no additional measurable motion reduction with the addition of the muscle relaxant. CONCLUSION The liver motion in each anesthetized dog was controlled under 3.0 mm in all directions with the use of high-frequency jet ventilation. No detectable advantage was identified by the injection of muscle relaxant in terms of further reducing the liver motion. The preclinical animal study indicated that the use of high-frequency jet ventilation (HFJV) would be able to limit the liver motion to an extent acceptable for the application of extracranial radiosurgery in humans. Radiosurgery for localized liver tumors warrants further investigation.
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Kwon DH, Lee M, Kim JJ, Kim JG, El-Zaatari FA, Osato MS, Graham DY. Furazolidone- and nitrofurantoin-resistant Helicobacter pylori: prevalence and role of genes involved in metronidazole resistance. Antimicrob Agents Chemother 2001; 45:306-8. [PMID: 11120984 PMCID: PMC90279 DOI: 10.1128/aac.45.1.306-308.2001] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The prevalence of furazolidone, nitrofurantoin, and metronidazole resistance among Helicobacter pylori strains was assessed with 431 clinical isolates. Fifty-two percent were metronidazole resistant, compared to 2% (7 of 431) with resistance to furazolidone and nitrofurantoin. All seven furazolidone- and nitrofurantoin-resistant isolates were also metronidazole resistant. rdxA, frxA, and fdxB knockouts did not result in furazolidone or nitrofurantoin resistance. These data suggest that furazolidone and nitrofurantoin may be good alternatives to metronidazole for treating H. pylori infection.
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Yang CH, Murti A, Pfeffer SR, Basu L, Kim JG, Pfeffer LM. IFNalpha/beta promotes cell survival by activating NF-kappa B. Proc Natl Acad Sci U S A 2000; 97:13631-6. [PMID: 11095741 PMCID: PMC17627 DOI: 10.1073/pnas.250477397] [Citation(s) in RCA: 128] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
IFNs play critical roles in host defense by modulating the expression of various genes via signal transducer and activator of transcription factors. We show that IFNalpha/beta activates another important transcription factor, NF-kappaB. DNA-binding activity of NF-kappaB was induced by multiple type 1 IFNs and was promoted by IFN in a diverse group of human, monkey, rat, and murine cells. Human IFN promoted NF-kappaB activation in murine cells that express the human IFNalpha/beta receptor-1 signal-transducing chain of the type 1 IFN receptor. IFN promotes inhibitor of kappa B alpha (IkappaBalpha) serine phosphorylation and degradation, and stimulates NF-kappaB DNA-binding and transcriptional activity. Importantly, IFN promotes cell survival by protecting cells against a variety of proapoptotic stimuli, such as virus infection and antibody-mediated crosslinking. Expression of superrepressor forms of IkappaBalpha, besides inhibiting IFN-mediated NF-kappaB activation and IkappaBalpha degradation, also enhanced apoptotic cell death in IFN-treated cells. We conclude that NF-kappaB activation by IFNalpha/beta is integrated into a signaling pathway through the IFNalpha/beta receptor-1 chain of the type 1 IFN receptor that promotes cell survival in apposition to various apoptotic stimuli.
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Kim JS, Lee WK, Rim JA, Jensen WP, Lee JH, Kim MJ, Kim JG, Suh IH. 25,27-(6-Tosyl-3,9-dioxa-6-azaundecane-1,11-diyldioxy)-26,28-(3,6, 9-trioxaundecane-1,11-diyldioxy)calix[4]arene. Acta Crystallogr C 2000; 56 Pt 11:1369-71. [PMID: 11077302 DOI: 10.1107/s0108270100010921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2000] [Accepted: 08/07/2000] [Indexed: 11/10/2022] Open
Abstract
A new calix[4]-crowned azacrown ether, C(51)H(59)NO(11)S, consisting of four phenyl rings in a 1,3-alternate conformation was synthesized from the reaction of 25, 27-bis(5-chloro-3-oxapentyloxy)calix[4]crown-5 and p-toluenesulfonamide in the presence of Cs(2)CO(3). A crown-5 loop was attached on the two facing lower rims of the calix[4]arene and the N-tosyl azacrown group was attached on the other set of lower rims of the calix[4]arene backbone. This molecule seems to offer an inside cavity for the formation of a host-guest complex.
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