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Pratt DK, Kim MG, Kreyssig A, Lee YB, Tucker GS, Thaler A, Tian W, Zarestky JL, Bud'ko SL, Canfield PC, Harmon BN, Goldman AI, McQueeney RJ. Incommensurate spin-density wave order in electron-doped BaFe2 As2 superconductors. PHYSICAL REVIEW LETTERS 2011; 106:257001. [PMID: 21770663 DOI: 10.1103/physrevlett.106.257001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2011] [Indexed: 05/31/2023]
Abstract
Neutron diffraction studies of Ba(Fe(1-x)Co(x))(2)As)(2) reveal that commensurate antiferromagnetic order gives way to incommensurate magnetic order for Co compositions between 0.056 < x < 0.06. The incommensurability has the form of a small transverse splitting (0, ± ε, 0) from the commensurate antiferromagnetic propagation vector Q(AFM) = (1,0,1) (in orthorhombic notation) where ε ≈ 0.02-0.03 and is composition dependent. The results are consistent with the formation of a spin-density wave driven by Fermi surface nesting of electron and hole pockets and confirm the itinerant nature of magnetism in the iron arsenide superconductors.
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Shim HJ, Park CH, Kim MG, Lee SK, Yeo SG. A pre- and postoperative bacteriological study of chronic suppurative otitis media. Infection 2010; 38:447-52. [PMID: 20700754 DOI: 10.1007/s15010-010-0048-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2010] [Accepted: 07/21/2010] [Indexed: 11/27/2022]
Abstract
BACKGROUND Although many bacteriological studies on preoperative otorrhea in patients with chronic suppurative otitis media (CSOM) have been performed, there are few studies on postoperative otorrhea. In this study, we analyzed the pathogenic microorganisms, changes in the bacterial species before and after surgery, and the antibiotic sensitivity on preoperative and postoperative cultures. METHODS This was a retrospective study of 87 postoperative otorrhea patients who were part of a sample of 1,754 patients with CSOM who underwent tympanomastoidectomy; preoperative and postoperative otorrhea samples were obtained from January 2002 to April 2009. We analyzed patients with postoperative otorrhea divided into two groups: those with early onset (<3 months after surgery, n = 45) and those with late onset (>3 months after surgery, n = 42) otorrhea. RESULTS Four species of organisms, methicillin-sensitive Staphylococcus aureus (MSSA), methicillin-resistant S. aureus (MRSA), Pseudomonas, and coagulase-negative Staphylococcus (CNS), showed higher prevalence than others on both the preoperative and postoperative cultures. When we compared the early and late onset otorrhea groups, we found that 'no growth' was significantly higher in the early onset group (n = 19 vs. n = 5), whereas MSSA was significantly higher in the late onset group (n = 1 vs. n = 12). Of the 67 patients with positive preoperative cultures, 15 (22.4%) had the same bacteria after surgery, 34 (50.8%) had other bacteria, 2 (3.0%) had fungi, and 16 (23.8%) showed no growth on postoperative bacteriological testing. MSSA (9%) and MRSA (16.7%) were rarely recultured after surgery, whereas Pseudomonas was recultured frequently (61.5%). CONCLUSION Unlike MSSA and MRSA, ciprofloxacin-resistant P. aeruginosa (CRP) occasionally causes early onset postoperative otorrhea due to the lack of highly potent antibiotics against this species. The success rate of infection control by surgery and antibiotics was low for CRP.
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Nandi S, Kim MG, Kreyssig A, Fernandes RM, Pratt DK, Thaler A, Ni N, Bud'ko SL, Canfield PC, Schmalian J, McQueeney RJ, Goldman AI. Anomalous suppression of the orthorhombic lattice distortion in superconducting Ba(Fe1-xCox)2As2 single crystals. PHYSICAL REVIEW LETTERS 2010; 104:057006. [PMID: 20366790 DOI: 10.1103/physrevlett.104.057006] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2009] [Indexed: 05/29/2023]
Abstract
High-resolution x-ray diffraction measurements reveal an unusually strong response of the lattice to superconductivity in Ba(Fe1-xCox)2As2. The orthorhombic distortion of the lattice is suppressed and, for Co doping near x=0.063, the orthorhombic structure evolves smoothly back to a tetragonal structure. We propose that the coupling between orthorhombicity and superconductivity is indirect and arises due to the magnetoelastic coupling, in the form of emergent nematic order, and the strong competition between magnetism and superconductivity.
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Kim JH, Gramatica P, Kim MG, Kim D, Tratnyek PG. QSAR modelling of water quality indices of alkylphenol pollutants. SAR AND QSAR IN ENVIRONMENTAL RESEARCH 2007; 18:729-743. [PMID: 18038370 DOI: 10.1080/10629360701698761] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The aim of this study was to determine the degradability of 26 Alkylphenols (APs) by Chemical Oxygen Demand (COD) and/or 5-day Biochemical Oxygen Demand (BOD(5)), and to describe these data from Quantitative Structure-activity Relationships (QSARs). Statistical analysis techniques, such as Multiple Linear Regression (MLR), Principal Component Regression (PCR), Partial Least-Squares (PLS) Regression and Neural Network (NN) were carried out to calibrate and validate four-descriptor QSAR models using two different types of descriptor sets. Stable MLR-QSAR models using Leave-One-Out (LOO) were obtained with high predictability performance: r(2) = 0.924, Q(2)(cv) =0.854 for log (1/BOD) model on 24 APs and r(2) = 0.888, Q(2)(cv) = 0.818 for log (1/COD) on all the studied APs. The MLR models, built with four Dragon descriptors selected by Genetic Algorithm (GA), presented the following performances on 24 APs: r(2) = 0.889, Q(2)(cv) = 0.848 for log (1/BOD(5)) and r(2) = 0.885, Q(2)(cv) = 0.834 for log (1/COD) on 26 compounds. From these results, it is expected that the QSAR models generated could be successfully expanded to predict the biological and chemical activities of structurally diverse AP compounds.
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Rho MH, Kim DW, Kwon JS, Lee SW, Sung YS, Song YK, Kim MG, Kim SG. OK-432 sclerotherapy of plunging ranula in 21 patients: it can be a substitute for surgery. AJNR Am J Neuroradiol 2006; 27:1090-5. [PMID: 16687549 PMCID: PMC7975734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
BACKGROUND AND PURPOSE Although first-choice therapy for the ranula is surgery, this choice presents technical difficulties and frequent recurrences because of insufficient surgery. We evaluated the efficacy of OK-432 sclerosis of the plunging ranula as a substitute for surgery. METHODS Twenty-one patients with plunging ranula were treated with intralesional injection of OK-432. The liquid content of the ranula was aspirated as much as possible, after which OK-432 solution was injected in the same volumes as that drawn out. Patients were followed on sonography or CT. RESULTS Seven (33.3%) patients with plunging ranulas showed total shrinkage and resolution, and 4 (19%) patients showed near-total shrinkage (more than 90% of the volume). Four (19%) patients revealed marked shrinkage (more than 70% of the volume), and 3 (14.3%) patients showed partial shrinkage (less than 70% of the volume). Three (14.3%) patients showed recurrence after total shrinkage 1 month after injection. The overall recurrence rate after each injection was 47% (16 of 34 injections in 21 patients), but the recurrence rate after the last sclerotherapy was only 14%. There were no serious side effects except for fever lasting 2-3 days (12 patients) and swelling (10 patients) for 3-5 days. Mild odynophagia for 1-2 days was also noted in 7 patients, and there was 1 severe case of odynophagia. CONCLUSION OK-432 sclerotherapy of plunging ranula is a safe and potentially curative procedure that may be used as a primary treatment for plunging ranula before considering surgery.
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Chon U, Jang HM, Kim MG, Chang CH. Layered perovskites with giant spontaneous polarizations for nonvolatile memories. PHYSICAL REVIEW LETTERS 2002; 89:087601. [PMID: 12190499 DOI: 10.1103/physrevlett.89.087601] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2001] [Indexed: 05/23/2023]
Abstract
A series of titanate-based layered perovskites having large values of the spontaneous polarization P(s) were developed for their applcations to nonvolatile ferroelectric random access memories. Among these, the Nd-modified bismuth titanate [Bi(4-x)Nd(x)Ti(3)O(12) (BNdT)] system exhibited the most remarkable ferroelectric properties. The c-axis oriented BNdT capacitor was characterized by a switchable remanent polarization 2P(r) of over 100 microC/cm(2) and imprinting and fatigue-free behavior. The active Ti site responsible for the giant P(s) was identified with the help of Rietveld analysis, x-ray absorption near-edge structure study, and ab initio quantum computations.
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Kim MG, Kim BH, Choi JA, Lee NJ, Chung KB, Choi YS, Cho SB, Lim HC. Intra-articular ganglion cysts of the knee: clinical and MR imaging features. Eur Radiol 2002; 11:834-40. [PMID: 11372618 DOI: 10.1007/s003300000713] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The purpose of this study was to present clinical and MR imaging features of intra-articular ganglion cysts of the knee. Retrospective review of 1685 consecutive medical records and MR examinations of the knee performed at three imaging centers allowed identification of 20 patients (13 men and 7 women; mean age 35 years), in whom evidence of intra-articular ganglion cyst was seen. Of the 20 ganglion cysts, 5 were found in the infrapatellar fat pad, 10 arose from the posterior cruciate ligament, and 5 from the anterior cruciate ligament. Three of five patients with ganglion cyst in the infrapatellar fat pad had a palpable mass. In 7 of 15 patients with ganglion cyst in the intercondylar notch, exacerbation of pain occurred in a squatting position. On four MR arthrographies, ganglion cysts were an intra-articular round, lobulated, low signal intensity lesion. Five cases of fat-suppressed contrast-enhanced T1-weighted SE images demonstrated peripheral thin rim enhancement. The clinical presentation of intra-articular ganglion cyst is varied according to its intra-articular location. The MR appearance of intra-articular ganglion cyst is characteristic and usually associated with the cruciate ligament or the infrapatellar fat pad. Magnetic resonance arthrography has no definite advantage over conventional MR in the evaluation of the lesion. For intra-articular ganglion cyst in the infrapatellar fat pad, fat-suppressed contrast-enhanced MR imaging could be useful, because a thin, rim-enhancing feature of intra-articular ganglion cyst allows it to be distinguished from synovial hemangioma and synovial sarcoma.
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Lee G, Kim MG, Yim JB, Hong SH. Alternative transcriptional initiation and splicing of mouse Lamc2 message. Mol Cells 2001; 12:380-90. [PMID: 11804339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
To investigate the mechanism of two forms of messages (5.1 and 2.4 kb) in mouse Lamc2, a gene encoding for the gamma2 chain of epithelial cell-specific laminin 5, we analyzed approximately 40 kb of genomic DNA containing the sequences from the first intron to the 23rd exon to the 3' untranscribed region. With the 5' rapid amplification of cDNA end (RACE) and primer extension technique using RNA from mouse kidney and thymic epithelial cells, we found that the smaller message starts at the 2895th base of the cDNA within the 19th exon. Upstream sequences of this alternative start site showed the promoter activity in the reporter assay with the secreted form of alkaline phosphatase (SEAP). We also identified a novel alternatively spliced exon (exon 19B) that includes two stop codons. These results revealed two possible additional open reading frame that are different from the previously described alternative human gamma2 peptide. Therefore, the mechanism for generating smaller message and the event of alternative splicing are quite distinct between mouse and human Lamc2, although genomic organization is highly conserved. The significance of the presence of alternative message is discussed.
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Cho EG, Kim MG, Kim C, Kim SR, Seong IS, Chung C, Schwartz RH, Park D. N-terminal processing is essential for release of epithin, a mouse type II membrane serine protease. J Biol Chem 2001; 276:44581-9. [PMID: 11567025 DOI: 10.1074/jbc.m107059200] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Epithin was originally identified as a mouse type II membrane serine protease. Its human orthologue membrane type-serine protease 1 (MT-SP1)/matriptase has been reported to be localized on the plasma membrane. In addition, soluble forms of matriptase were isolated from human breast milk and breast cancer cell-conditioned medium. In this paper, we report a processing mechanism that appears to be required for the release of epithin. CHO-K1 or COS7 cells transfected with single full-length epithin cDNA generated two different-sized proteins in cell lysates, 110 and 92 kDa. The 92-kDa epithin was found to be an N-terminally truncated form of the 110-kDa epithin, and it was the only form detected in the culture medium. The 92-kDa epithin was also found on the cell surface, where it was anchored by the N-terminal fragment. The results of in vivo cell labeling experiments indicate that the 110-kDa epithin is rapidly processed to the 92-kDa epithin. Using site-directed mutagenesis experiments, we identified Gly(149) of the GSVIA sequence in epithin as required for the processing and release of the protein. These results suggest that N-terminal processing of epithin at Gly(149) is a necessary prerequisite step for release of the protein.
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Jo D, Lyu MS, Cho EG, Park D, Kozak CA, Kim MG. Identification and genetic mapping of the mouse Fkbp9 gene encoding a new member of FK506-binding protein family. Mol Cells 2001; 12:272-5. [PMID: 11710534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023] Open
Abstract
We have isolated a gene from a cDNA library generated from the thymus of a mouse with severe combined immune deficiency, termed FKBP9, that encodes a protein related to FK506-binding protein 6 (65 kDa, FKBP65). FKBP9 contains four peptidyl-prolyl cis-trans isomerase (PPIase) signature and two EF-hand domains which is identical to FKBP6/65 in overall structural organization. However, the two proteins share only 66% amino acid identity. FKBP9 is expressed at high levels in mouse heart, muscle, lung, and kidney. While FKBP6 was previously mapped to chromosome 11, the Fkbp9 gene was mapped to mouse chromosome 6 by analysis of a multilocus cross. These results identify a new member of the mouse FKBP protein family located on a separate chromosome.
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Kim MG, Hong SJ, Son SJ, Song HJ, Kim IH, Oh CH, Moon JS. Quantitative histopathologic findings of erythromelanosis follicularis faciei et colli. J Cutan Pathol 2001; 28:160-4. [PMID: 11168770 DOI: 10.1034/j.1600-0560.2001.028003160.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: 11/23/2022]
Abstract
BACKGROUND Even though only 33 cases of Erythromelanosis follicularis faciei et colli (EFFC) have been reported around the world, there have been no quantitative clinicopathological studies yet. The purpose of this study is to examine quantitatively clinical and histopathological evaluations of EFFC using image analysis system. METHOD Clinical grading of its severity was assessed. Many parameters of the horny layer, granular layer, epidermis and the dermal components were measured and compared to controls by image analysis. The correlation between the histological findings and clinical grading was assessed. RESULT Thickness and compactness of the horny layer was significantly increased in EFFC. There were no significant differences in the number of melanocytes and severity of pigmentation between EFFC and controls; however, melanization was slightly increased in EFFC. The percent area of the superficial blood vessels was significantly increased and correlated with visual grading of erythema. Diameters of hair shafts and outer root sheaths, and thickness of inner root sheaths were decreased. Basal layer pigmentation was correlated with the clinical features of pigmentation. CONCLUSION This study supported the findings of hyperkeratosis and dilatation of superficial dermal blood vessels in EFFC. The pigmentation of the basal layer and the percent area of the inner spaces of the superficial dermal blood vessels may reflect the clinical severity more than the other parameters. Although follicular plugging is a characteristic clinical feature of EFFC, enlargement of hair follicles and hair shafts were not characteristic pathologic changes EFFC in our study.
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Oh HW, Kim MG, Shin SW, Bae KS, Ahn YJ, Park HY. Ultrastructural and molecular identification of a Wolbachia endosymbiont in a spider, Nephila clavata. INSECT MOLECULAR BIOLOGY 2000; 9:539-543. [PMID: 11029673 DOI: 10.1046/j.1365-2583.2000.00218.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Wolbachia-like bacteria were observed in the egg cells of golden orb-weaving spider, Nephila clavata, by means of transmission electron microscopy. The bacteria exhibited the typical morphology of Wolbachia, including three enveloping membranes. Based on the amplification and sequencing of partial 16S rDNA and ftsZ gene, the bacteria were identified as Wolbachia, intracellular, transovarially inherited alpha-proteobacteria in invertebrates. Phylogenetic analysis based on 16S rDNA and ftsZ gene sequences invariably indicated that the intracellular bacteria from N. clavata belonged to group A Wolbachia, which were found only from insects. Clustering of Wolbachia from N. clavata with group A Wolbachia indicates that the bacteria were probably transferred horizontally between insects and the spider.
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Soh JW, Mao Y, Kim MG, Pamukcu R, Li H, Piazza GA, Thompson WJ, Weinstein IB. Cyclic GMP mediates apoptosis induced by sulindac derivatives via activation of c-Jun NH2-terminal kinase 1. Clin Cancer Res 2000; 6:4136-41. [PMID: 11051267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Sulindac sulfone (Exisulind) induces apoptosis and exhibits cancer chemopreventive activity, but in contrast to sulindac, it does not inhibit cyclooxygenases 1 or 2. We found that sulindac sulfone and two potent derivatives, CP248 and CP461, inhibited the cyclic GMP (cGMP) phosphodiesterases (PDE) 2 and 5 in human colon cells, and these compounds caused rapid and sustained activation of the c-Jun NH2-terminal kinase 1 (JNK1). Rapid activation of stress-activated protein/ERK kinase 1 (SEK1) and mitogen-activated protein kinase kinase kinase (MEKK1), which are upstream of JNK1, was also observed. Other compounds that increase cellular levels of cGMP also activated JNK1, and an inhibitor of protein kinase G (PKG), Rp-8-pCPT-cGMPS, inhibited JNK1 activation by the sulindac sulfone derivatives. Expression of a dominant-negative JNK1 protein inhibited CP248-induced cleavage of poly(ADP-ribose) polymerase, a marker of apoptosis. Thus, it appears that sulindac sulfone and related compounds induce apoptosis, at least in part, through activation of PKG, which then activates the MEKK1-SEK1-JNK1 cascade. These studies also indicate a role for cGMP and PKG in the JNK pathway.
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Aoki T, Hirono I, Kim MG, Katagiri T, Tokuda Y, Toyohara H, Yamamoto E. Identification of viral induced genes in Ig+ leucocytes of Japanese flounder Paralichthys olivaceus, by differential hybridisation with subtracted and un-subtracted cDNA probes. FISH & SHELLFISH IMMUNOLOGY 2000; 10:623-630. [PMID: 11081439 DOI: 10.1006/fsim.2000.0279] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Up-regulated genes of leucocytes expressing immunoglobulin (Ig+ leucocytes) of hirame rhabdovirus (HRV)-infected Japanese flounder were identified by differential hybridisation, using subtracted and un-subtracted cDNA probes. Ig+ leucocytes were separated from apparently healthy and HRV-infected Japanese flounder by the magnetic beads antibody method using mouse anti-Japanese flounder Ig monoclonal antibody (mab). A cDNA library was constructed from HRV-infected Japanese flounder leucocytes, and was screened with subtracted cDNA probes enriched in genes up-regulated by HRV infection. Fifty cDNAs were isolated for further analysis. These included cDNAs coding for homologues of interferon-inducible 56K protein (IFI56), Stat3, CEF-10, RGS5, inducible poly(A) binding protein, prolylcarboxylpeptidase, basigin III (Ig superfamily), MUC-18 (Ig superfamily), proteasome-nexin 1 (SERPIN), herpes virus entry mediator (TNFR family), collagenase III, gelatinase-b, megakaryocyte stimulating factor, Rab8-interacting protein, IgM, IgD and 20 unknown cDNA clones. The majority of these identified genes are reported for the first time in fish. From leucocytes mRNA for homologues of IFI56, CEF-10, Stat3, SERPIN and inducible poly (A) binding protein expression was shown to increase following HRV infection.
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Chen C, Kim MG, Soo Lyu M, Kozak CA, Schwartz RH, Flomerfelt FA. Characterization of the mouse gene, human promoter and human cDNA of TSCOT reveals strong interspecies homology. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1493:159-69. [PMID: 10978518 DOI: 10.1016/s0167-4781(00)00177-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The regulation of gene expression in thymic epithelial cells is critical for T cell development. The mouse thymic epithelial gene Tscot encodes a protein with weak homology to bacterial 12 transmembrane co-transporters. Using competitive reverse transcription-polymerase chain reaction (RT-PCR), we show that low level Tscot expression is detectable in several other tissues. Tscot was mapped to chromosome 4 and was also detected in other mammalian species by Southern blotting. The human cDNA clone showed 77% amino acid identity with the mouse sequence. The highest conservation was in the TM regions and in a small segment of the central cytoplasmic loop. Genomic clones spanning 17164 bases of the Tscot gene revealed four exons with nine of the TM domains encoded in the first exon. The major transcriptional start site in mouse was identified by a primer extension analysis and confirmed by RT-PCR. Comparison of 1.7 kb of the human and mouse promoters identified six conserved possible regulatory elements, one containing a potential binding site for an interferon alpha inducible factor. Finally, as a functional test, 3 kb of the murine promoter was used to create a transgenic mouse that expresses enhanced green fluorescent protein message strongly in the thymus, weakly in the kidney and undetectably in the spleen, liver and heart.
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Flomerfelt FA, Kim MG, Schwartz RH. Spatial, a gene expressed in thymic stromal cells, depends on three-dimensional thymus organization for its expression. Genes Immun 2000; 1:391-401. [PMID: 11196687 DOI: 10.1038/sj.gene.6363695] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Although the importance of thymic stroma in thymopoiesis has been recognized, the underlying molecular details regarding stromal cell biology remain obscure. To study this area, we have cloned genes expressed in thymic stromal cells. Spatial is alternatively spliced to generate two mRNAs in thymus and lymph node (LN) but it is not expressed in the spleen. In mouse embryos, the short form begins expression at day 10 while the long form is not detected until day 12. Both mRNAs encode proline rich proteins and their closest homology is to homeobox and POU domain transcription factors. Spatial is not expressed in thymocytes, but it is expressed in 2-deoxyguanosine-treated day 14 fetal thymic organ culture (FTOC) and in reaggregated FTOC. These data suggest that a normal three-dimensional organization of stromal cells is required for Spatial expression. An antiserum raised against a C-terminal peptide detected proteins of 38 and 32 kDa in Western blots of total thymus proteins. In frozen thymus sections, subcapsular epithelial cells were stained with the anti-Spatial antiserum. Paracortical subcapsular cells of unknown function were also stained in the LN. Both forms of Spatial fused to the green fluorescent protein (GFP) localize to the nucleus in transfected cells.
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Kim MG, Lee G, Lee SK, Lolkema M, Yim J, Hong SH, Schwartz RH. Epithelial cell-specific laminin 5 is required for survival of early thymocytes. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2000; 165:192-201. [PMID: 10861052 DOI: 10.4049/jimmunol.165.1.192] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The gene LamC2 encoding the gamma2 chain of laminin 5, an epithelial cell-specific extracellular matrix protein, was identified in a PCR-based subtracted cDNA library from mouse thymic stromal cells. The mRNA existed in two alternative forms (5.1 and 2.4 kb). The full-length message was highly expressed in SCID thymus and in a nurse cell line, but not in other thymic epithelial cell lines, while the short form was more widely expressed. In situ hybridization and immunohistochemical staining revealed laminin 5 expression mostly in the subcapsular region of the adult thymus. Addition to fetal thymic organ cultures of a cell adhesion-blocking mAb to the alpha3 chain of laminin 5 interrupted T cell development. There was a 40% reduction in the total yield of thymocytes, and the most profound decrease (75-90%) was seen in the CD25+CD44+ and CD25+CD44-subsets of the CD4-CD8- double negative fraction. Most of the surviving double negative thymocytes expressed Sca-1, and there were significant increases in the number of cells with CD69 expression and in the fraction of annexin V-stained cells. None of these changes were observed with a nonblocking anti-laminin alpha3 chain mAb. These results suggest that the interaction between double negative thymoctyes and laminin 5 made by subcapsular epithelial cells is required for the survival and differentiation of mouse thymocytes.
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MESH Headings
- Animals
- Antibodies, Blocking/pharmacology
- Antibodies, Monoclonal/pharmacology
- CD4-Positive T-Lymphocytes/cytology
- CD4-Positive T-Lymphocytes/immunology
- CD4-Positive T-Lymphocytes/metabolism
- CD8-Positive T-Lymphocytes/cytology
- CD8-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/metabolism
- Cell Adhesion Molecules/genetics
- Cell Adhesion Molecules/immunology
- Cell Adhesion Molecules/physiology
- Cell Death/immunology
- Cell Differentiation/immunology
- Cell Lineage/immunology
- Cell Survival/immunology
- Cells, Cultured
- Cloning, Molecular
- DNA, Complementary/isolation & purification
- Epithelial Cells/immunology
- Epithelial Cells/physiology
- Gene Library
- Growth Inhibitors/physiology
- Immunophenotyping
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Nude
- Mice, SCID
- Organ Culture Techniques
- Receptors, Antigen, T-Cell, alpha-beta/antagonists & inhibitors
- Receptors, Antigen, T-Cell, alpha-beta/physiology
- Stromal Cells/immunology
- Stromal Cells/metabolism
- T-Lymphocytes/cytology
- T-Lymphocytes/immunology
- Thymus Gland/anatomy & histology
- Thymus Gland/cytology
- Thymus Gland/immunology
- Thymus Gland/metabolism
- Kalinin
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Kim MG, Flomerfelt FA, Lee KN, Chen C, Schwartz RH. A putative 12 transmembrane domain cotransporter expressed in thymic cortical epithelial cells. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2000; 164:3185-92. [PMID: 10706709 DOI: 10.4049/jimmunol.164.6.3185] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
We have isolated a full-length cDNA clone (thymic stromal origin (TSO)-1C12) from a SCID thymus library using a probe from a PCR-based subtractive library enriched for sequences from fetal thymic stromal cells. TSO-1C12 mRNA is expressed mainly in the thymic cortex and is highly enriched in SCID thymus. Expression per cell is highest during fetal thymus development and decreases after day 16. Antipeptide Abs immunoprecipitated a hydrophobic, plasma membrane glycoprotein (thymic stromal cotransporter, TSCOT) whose translated sequence has weak homology to bacterial antiporters and mammalian cation cotransporters with 12 transmembrane domains. TSCOT represents a new member of this superfamily that is highly expressed in thymic cortical epithelial cells.
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Jew S, Kim HJ, Kim MG, Roh EY, Hong CI, Kim JK, Lee JH, Lee H, Park H. Synthesis and in vitro cytotoxicity of hexacyclic camptothecin analogues. Bioorg Med Chem Lett 1999; 9:3203-6. [PMID: 10576688 DOI: 10.1016/s0960-894x(99)00555-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A series of C(7)-N-alkylaminoethyl-C(10), C(11)-methylenedioxy- and ethylenedioxy-camptothecin (3a-g, 4a-b) were prepared. Their syntheses and in vitro cytotoxicity were reported. Among 15 derivatives, 3a and 3b showed more potent cytotoxicity than Camptothecin, especially in CAOV-3 cell line.
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Kim MG, Chen C, Lyu MS, Cho EG, Park D, Kozak C, Schwartz RH. Cloning and chromosomal mapping of a gene isolated from thymic stromal cells encoding a new mouse type II membrane serine protease, epithin, containing four LDL receptor modules and two CUB domains. Immunogenetics 1999; 49:420-8. [PMID: 10199918 DOI: 10.1007/s002510050515] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We cloned and sequenced a mouse gene encoding a new type of membrane bound serine protease (epithin) containing a multidomain structure. The initial cDNA clone was found previously in a polymerase chain reaction (PCR)-based subtractive library generated from fetal thymic stromal cells, and the message was shown to be highly expressed in a thymic epithelial nurse cell line. A clone isolated from a severe combined immunodeficiency (SCID) thymus library and extended to its full length at the 5' end with the RACE technique contains an open reading frame of 902 amino acids. Based on the sequence of this clone, the predicted protein structure is a type II membrane protein with a C-terminal serine protease domain linked to the membrane by four low density lipoprotein receptor modules and two CUB domains. High message expression by northern blotting was detected in intestine, kidney, lung, SCID, and Rag-2(-/-) thymus, and 2-deoxyguanosine-treated fetal thymic rudiment, but not in skeletal muscle, liver, heart, testis, and brain. Sorted MHC class II+ and II- fetal thymic stromal cells were positive for expression by reverse transcriptase-PCR, whereas CD45(+) thymocytes were not. The gene was found in chicken and multiple mammalian species under low stringency Southern hybridization conditions. Under high stringency conditions, only a single gene per haploid genome was identified in the mouse. This gene, Prss14 (protease, serine, 14), was mapped to mouse chromosome 9 and is closely linked to the Fli1 (Friend leukemia integration 1) gene.
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Lee C, Kim MG, Jeon SH, Park DE, Park SD, Seong RH. Two species of mRNAs for the fyn proto-oncogene are produced by an alternative polyadenylation. Mol Cells 1998; 8:746-9. [PMID: 9895129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
Two mRNA species with different sizes (3.8 kb and 2.8 kb) for the fyn proto-oncogene have been noticed during Northern hybridization analysis. However, the difference between the two mRNA species has not been resolved yet. By screening a phage expression library using the monoclonal antibody (mAb) B16-5 which recognizes Src homology 3 (SH3) domains of phospholipase C-gamma and Nck, we have cloned a cDNA encoding the larger species of fyn mRNA. The size of the clone was 3.5 kb and DNA sequencing analysis of the clone showed that it was fyn expressed mainly in T-cells, fyn (T), with an untranslated region 1 kb longer than the previously reported one. The 3'-end fragment of the clone hybridized only to the larger species (3.8 kb) of fyn mRNA but not to the smaller one (2.8 kb) on Northern blot analysis. Furthermore, an additional polyadenylation signal sequence was found at the end of this clone. These results indicate that the two mRNA species for fyn are produced by alternative polyadenylation.
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Song KB, Seo JW, Kim MG, Rhee SK. Levansucrase of Rahnella aquatilis ATCC33071. Gene cloning, expression, and levan formation. Ann N Y Acad Sci 1998; 864:506-11. [PMID: 9928133 DOI: 10.1111/j.1749-6632.1998.tb10369.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Shin SW, Park SS, Park DS, Kim MG, Kim SC, Brey PT, Park HY. Isolation and characterization of immune-related genes from the fall webworm, Hyphantria cunea, using PCR-based differential display and subtractive cloning. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 1998; 28:827-837. [PMID: 9818384 DOI: 10.1016/s0965-1748(98)00077-0] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Following injection of bacteria into the hemocoel of the fall webworm, Hyphantria cunea, several inducible genes were identified and characterized using PCR-based differential display (DD-PCR) and subtractive cloning. Ten immune-related cDNA clones (Hdd1, Hdd2, Hdd3, Hdd11, Hdd13, Hdd15, Hdd17, Hdd23, Hs106, Hs302) were isolated and characterized. The deduced amino acid sequence of Hdd2 was shown to be a member of the copper, zinc superoxide dismutase (Cu-Zn SOD) family. The H. cunea Cu-Zn SOD is novel in that it is up-regulated following a bacterial challenge and has a putative signal peptide suggesting its secretion and involvement in the insect immune response. Hdd3 was found to encode a new member of the serpin (serine protease inhibitor) family. The putative lectin corresponding to Hdd15 is of a different kind in that it has two lectin C domains in a single molecule. These two lectin C domains show significant homology to the lectin C domain of Periplaneta lipopolysaccharide binding protein (LPS-BP). Three cloned genes, Hdd17, Hs106 and Hs302, encode a homologue to Bombyx mori Gram negative binding protein, a hemolin-like protein and a attacin-like protein, respectively. The deduced amino acid sequences from Hdd11 showed weak homology with a Locusta migratoria hemolymph protein. On the contrary, Hdd1, Hdd13 and Hdd23 did not reveal any significant homology with known proteins. All of the 10 genes were clearly inducible by E. coli and M. luteus injection. Injection of distilled water only slightly induced mRNA levels. Comparison of temporal mRNA expression following E. coli injection showed three types of expression patterns.
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Jew SS, Kim MG, Kim HJ, Rho EY, Park HG, Kim JK, Han HJ, Lee H. Synthesis and in vitro cytotoxicity of C(20)(RS)-camptothecin analogues modified at both B (or A) and E ring. Bioorg Med Chem Lett 1998; 8:1797-800. [PMID: 9873436 DOI: 10.1016/s0960-894x(98)00317-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A series of C(7) and C(20)-substituted camptothecin derivatives (12-14, 16-18) are prepared. Their syntheses and in vitro cytotoxicities are reported.
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Kim MG, Chen C, Flomerfelt FA, Germain RN, Schwartz RH. A subtractive PCR-based cDNA library made from fetal thymic stromal cells. J Immunol Methods 1998; 213:169-82. [PMID: 9692849 DOI: 10.1016/s0022-1759(98)00031-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We describe our initial approach to clone and characterize genes expressed preferentially in thymic stromal cells, in an attempt to generate molecular reagents to study the role of these cells in thymopoiesis and thymic function. Thymic stromal cells were prepared from fetal thymic organ cultures by treating them with 2-deoxyguanosine and depleting the remaining hematopoietic cells with anti-CD45 antibody. A cDNA library was then prepared after subtraction and amplification by PCR. The cloned inserts were sequenced and compared for homology with known genes in the data base. Unidentified cDNAs were then examined for expression in normal and SCID thymus and in a set of SV40-transformed thymic epithelial cell lines, by Northern blotting and a dot blot assay. In this report we describe the development of the library and present a general description of the genes identified from the initial 249 cDNAs sequenced. Among these, a relatively high percentage (55%) do not show any homology to previously identified genes. Several genes with a limited expression pattern were selected for further study.
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