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Yuuichi S, Lee U, Takagi S, Konishi H, Maegawa J. P.123 Usefulness of submental island flap for reconstruction. J Craniomaxillofac Surg 2008. [DOI: 10.1016/s1010-5182(08)71911-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Biagi JJ, Oza AM, Grimshaw R, Ellard SL, Lee U, Sederias J, Ivy SP, Eisenhauer EA. A phase II study of sunitinib (SU11248) in patients (pts) with recurrent epithelial ovarian, fallopian tube or primary peritoneal carcinoma - NCIC CTG IND 185. J Clin Oncol 2008. [DOI: 10.1200/jco.2008.26.15_suppl.5522] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Yoo Y, Kim Y, Yoo H, Lee U. Targeting quantum dots to surface proteins in living cells. FASEB J 2008. [DOI: 10.1096/fasebj.22.1_supplement.583.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Kim Y, Yoo Y, Yoo H, Yoo C, Lee U. Neural Precursor cells (NPCs) derived from cervical and upper thoracic spinal cord. FASEB J 2008. [DOI: 10.1096/fasebj.22.1_supplement.974.5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Yoo H, Yoo Y, Kim Y, Lee U. Human embryonic stem cells can differentiate into myocytes with structural and functional properties of cardiomyocytes. FASEB J 2008. [DOI: 10.1096/fasebj.22.1_supplement.576.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Yoo YM, Lee CJ, Lee U, Kim YJ. Mitochondrial DNA in patients with essential tremor. Neurosci Lett 2008; 434:29-34. [PMID: 18262358 DOI: 10.1016/j.neulet.2008.01.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2007] [Revised: 12/19/2007] [Accepted: 01/11/2008] [Indexed: 10/22/2022]
Abstract
Essential tremor (ET) is one of the most common of the movement disorders. However, there has been little agreement in the neurological literature regarding diagnostic criteria for ET. It is not clear to what extent ET is associated with defects of mitochondrial DNA. In this study, we analyzed mitochondrial DNA (mtDNA) from the blood cells of the normal and ET patients using the long and accurate polymerase chain reaction (LA-PCR) and PCR. The large deletions were detected within several regions of mtDNA, but were not detected in the D-loop or CO I regions in ET patients. From our study, it is suggested that ET is a disorder showing a deficiency of mtDNA multicomplexes, and it also appears that mitochondrial dysfunction could be one of the causative factors of ET.
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Sasakura Y, Lee U, Ohmi Y, Kubota N. P.234 A case of rhabdomyosarcoma of upper jaw in adult. J Craniomaxillofac Surg 2006. [DOI: 10.1016/s1010-5182(06)60742-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Yoo YM, Lee CJ, Lee U, Kim YJ. Neuroprotection of adenoviral-vector-mediated GDNF expression against kainic-acid-induced excitotoxicity in the rat hippocampus. Exp Neurol 2006; 200:407-17. [PMID: 16690057 DOI: 10.1016/j.expneurol.2006.02.132] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2005] [Revised: 02/04/2006] [Accepted: 02/24/2006] [Indexed: 01/05/2023]
Abstract
Glial-cell-line-derived neurotrophic factor (GDNF) is a potent survival factor for several types of neurons. In the present study, we examined the protective roles of adenoviral-vector-delivered GDNF (Ad-GDNF) in the hippocampus damaged by kainic-acid (KA)-induced excitotoxicity using GAD-67 immunoreactivity, immunoblot analysis, behavioral test, 5-bromo-2-deoxyuridine (BrdU) and TUNEL assay. Ad-GDNF was pre-inoculated into the KA-treated rat hippocampus 7 days before KA injection. Ad-GDNF resulted in the suppression of KA-induced tonic-clonic convulsions. In situ apoptosis assay demonstrated a significant reduction in apoptotic cells in the CA3 and dentate hilus regions of the Ad-GDNF-pre-inoculated rats (Ad-GDNF-KA), compared to the KA rats. Striking reductions in the density of GAD-67 neurons were also observed in the CA3 and dentate hilus regions of the KA rats. On the other hand, the number of GAD-67-positive cells was recovered to the control levels in the Ad-GDNF-KA rats. Immunoblot analysis further confirmed that GAD-67 and Bcl-2 expression increased in the Ad-GDNF-KA rats compared to KA rats. Taken together, these results suggest that Ad-GDNF may serve to control KA-induced hippocampal cell loss and behavioral seizure.
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Yoo YM, Kim YJ, Lee U. The change of the neuron–glia differentiation rate in human neural precursor cells (HPCs) and Ad-BDNF-/-GDNF-infected HPCs following the administration of a neurotoxin. Neurosci Lett 2005; 387:100-4. [PMID: 16081212 DOI: 10.1016/j.neulet.2005.06.043] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2005] [Revised: 06/07/2005] [Accepted: 06/22/2005] [Indexed: 10/25/2022]
Abstract
Neurotrophic factors promote the survival of various neurons, including peripheral autonomic and sensory neurons, as well as central motor and dopamine neurons, and it is expected that they could function as therapeutic agents for neurodegenerative disease. We examined the changes in the neuron-glia differentiation rate in normal human neural precursor cells (HPCs), Ad-BDNF- and Ad-GDNF-infected HPCs following their treatment with 6-OHDA. We isolated the precursor cells from the human fetal midbrain. To investigate the expression of differentiated cell markers within neurons and glia after 6-OHDA-induced toxicity in HPCs, immunocytochemistry was performed. Our results showed that the treatment with 6-OHDA (100, 200, 300, 400 and 500 microM) for 24 h decreased the viability of the HPCs in vitro. Among the growth factors tested, BDNF and GDNF protected the HPCs against 6-OHDA-induced toxicity. Approximately, 5.8+/-2.2% and 0.5+/-0.1% of the HPCs treated with 6-OHDA were positive for the neuron marker, MAP2, and the oligodendrocyte marker, GalC, respectively, while 13.8+/-3.2% and 1.1+/-0.36% of the Ad-BDNF- or Ad-GDNF-infected HPCs treated with 6-OHDA stained positive for MAP2 and GalC, respectively. These results suggest that cocktail therapy using human precursor cells (HPCs) and certain neurotrophic factors (BDNF, GDNF) provide direct protection against 6-OHDA-induced toxicity and has an effect on the differentiation rate.
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Lê LH, Swenerton KD, Elit L, Provencher DM, Stuart GCE, LE T, Lee U, Rodgers A, Pond GR, Hu H, Oza AM. Phase II multicenter open-label study of carboplatin and pegylated liposomal doxorubicin in uterine and cervical malignancies. Int J Gynecol Cancer 2005; 15:799-806. [PMID: 16174227 DOI: 10.1111/j.1525-1438.2005.00139.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The results of a multicenter phase II study investigating carboplatin and pegylated liposomal doxorubicin (PLD) in patients with recurrent/metastatic uterine and cervical malignancies (UCM) are presented here. Fifty-three subjects with measurable, untreated, advanced UCM were enrolled. Fifty-one were evaluable for response. Prior combined-modality treatment was permitted if a component of primary therapy. Patients received carboplatin AUC = 5 with PLD 35 mg/m(2) intravenously once every 4 weeks. Overall response rate was 33% (35% stable disease). Overall survival (OS) at six months was 86% (95% CI 76%-96%). Six-month progression-free survival (PFS) was 43% (95% CI 30%-57%). Median PFS was 22.9 weeks (range 16.0-35.3) and median OS was 49.1 weeks (range 41.4-75.1). The most frequent grade 3-4 nonhematological adverse events were: abdominal pain (n = 7), fatigue (4), vomiting (4), nausea (3), and shortness of breath (3). There was 1 report of grade 3 hand-foot syndrome and none of grade 4. Twelve patients had first infusion reactions with only 1 discontinuing treatment. Grade 3-4 neutropenia occurred in 26/230 cycles (11.3%). There were no treatment-related deaths. The combination of carboplatin and PLD is well tolerated with sufficient activity to justify additional evaluation in clinical trials and might be suited to the addition of a taxane.
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Yoo YM, Lee U, Kim YJ. Apoptosis and nestin expression in the cortex and cultured astrocytes following 6-OHDA administration. Neurosci Lett 2005; 382:88-92. [PMID: 15911127 DOI: 10.1016/j.neulet.2005.02.070] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2004] [Revised: 02/22/2005] [Accepted: 02/24/2005] [Indexed: 11/19/2022]
Abstract
We used the dopaminergic neurotoxicant, 6-hydroxydopamine (6-OHDA), as a tool to characterize the origins of the astrocytic response to injury. Reactive astrocytes were examined by immunocyto- and histo-chemical visualization of nestin protein in the brain and cultivated cells. Following 6-OHDA (dose-dependent) treatment, the expression of nestin-like immunoreactive cells in the corpus callosum and cerebral cortex was increased compared with that of the control animals, indicating that a significant up-regulation of nestin protein occurred in these regions. In the corpus callosum and cerebral cortex, the majority of the nestin-like immunoreactive cells showed a distribution and pattern similar to those of the glial fibrillary acid protein (GFAP)-immunoreactive cells. Double immunofluorescence measurements showed that 100% of the nestin-like immunoreactive cells expressed GFAP-immunoreactive cells, indicating that these nestin-like immunoreactive cells belong to a reactive population of the astrocytes. In this study, we observed the morphological changes in the astrocytes following 6-OHDA administration, demonstrating that 6-OHDA induced injury leads to a rapid and transient up-regulation of nestin-like immunoreactivity in activated astrocytes.
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Kim YJ, Lee CJ, Lee U, Yoo YM. Tamoxifen-induced cell death and expression of neurotrophic factors in cultured C6 glioma cells. J Neurooncol 2005; 71:121-5. [PMID: 15690126 DOI: 10.1007/s11060-004-0984-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The effects of ( Z)-2[ p -(1,2-diphenyl-1-butenyl)phenoxy]-N ,N -dimethylamine citrate (tamoxifen) on cell survival and the expression of neurotrophic factors (NTF) were investigated in rat C6 glioma cells (C6). C6 cells do not express the estrogen receptor. Cytotoxic effect was detected from 24 h after the treatment with 10 microM tamoxifen and increased with time in a dose-dependent manner. C6 cells treated with tamoxifen also displayed various morphological types such as elliptical, round and aggregated form. As the treatment time increased, the proliferation of C6 cells was reduced remarkably and most of them became the round or aggregated form. To examine the relationship of the expression of NTF and the cytotoxicity of tamoxifen, the mRNA level of brain-derived neurotrophic factor (BDNF), glial-derived neurotrophic factor (GDNF), and basic fibroblast growth factor (bFGF) was measured after 24 h treatment with tamoxifen by RT-PCR. The expression of mRNA of BDNF or GDNF in C6 cells treated with various concentrations of tamoxifen was comparable to controls. The expression of bFGF mRNA was significantly reduced in C6 cells treated with 10 or 15 microM tamoxifen. The results suggest that tamoxifen exerts cytotoxic effect on estrogen receptor-negative C6 cells through the inhibition of the transcription of bFGF.
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Yoo YM, Kim YJ, Lee U, Paik DJ, Yoo HT, Park CW, Kim YB, Lee SG, Kim WK, Yoo CJ. Neurotrophic factor in the treatment of Parkinson disease. Neurosurg Focus 2003; 15:ECP1. [PMID: 15355014 DOI: 10.3171/foc.2003.15.1.12] [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: 11/06/2022]
Abstract
Object
Parkinson disease (PD) is a well-known degenerative disease resulting in the depletion of dopamine-producing neurons in the pars compacta of the substantia nigra. Adenoviral vector delivery of neurotrophic factors may provide a potential therapy for PD. The authors examined whether glial cell line–derived neurotrophic factor (GDNF) delivered via adenoviral vector (Ad-GDNF) could promote functional recovery in a rat model of PD. Additionally, they examined whether neural precursor cells (NPCs) provide the therapeutic potential of cultured neural cells for cell regeneration and replacement in PD.
Methods
All animals underwent stereotactic injection of 6-hydroxydopamine into the right substantia nigra. Eight weeks later, the rats were tested for apomorphine-induced rotational asymmetry and evaluation of explanted grafts infected with the complementary DNA for GDNF containing NPCs and NPCs alone. In the NPC cultures of embryonic rat striata, the authors found that basic fibroblast growth factor induced the proliferation of stem cells, which give rise to spheres of undifferentiated cells that generate neurons and glia.
Conclusions
In this study the authors found that the reduction of apomorphine-induced rotation was more prominent in parkinsonian rats that received Ad-GDNF-treated grafts containing NPCs (61%) than in those that received grafts of NPCs alone (16%).
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Matsumoto G, Sasakuri K, Tsukinoki K, Ohmi Y, Lee U, Shindo J. Growth of human squamous cell carcinoma xenografts in mice is inhibited by local angiostatin gene therapy. Oral Oncol 2002; 38:543-8. [PMID: 12167431 DOI: 10.1016/s1368-8375(01)00126-9] [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: 11/16/2022]
Abstract
The possibility of inhibiting tumor growth by blocking the formation of new tumor vessels has recently received attention. Antiangiogenic tumor therapies have recently attracted intense interest because of their direct endothelial targeting and the absence of drug resistance. Local antiangiogenic gene therapy for cancer offers a potential way to achieve sustained therapeutic release of antiangiogenic substances. As a step toward this goal, we used liposomes complexed to angiostatin cDNA and targeted to human squamous cell carcinoma cell lines in vivo. Tumor cells expressing angiostatin after local gene transfer showed markedly reduced vascularity and contained many apoptotic tumor cells. These results demonstrate the potential utility of liposome-derived angiostatin for adjuvant therapy of oral cancer in humans.
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Lee U, Hong JS, Choi JK, Kim KC, Kim YS, Curtis IS, Nam HG, Lim PO. Broad bean wilt virus Causes Necrotic Symptoms and Generates Defective RNAs in Capsicum annuum. PHYTOPATHOLOGY 2000; 90:1390-1395. [PMID: 18943381 DOI: 10.1094/phyto.2000.90.12.1390] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
ABSTRACT A virus was isolated from hot pepper (Capsicum annuum cv. Hyang Chon) growing in Korea and displaying necrotic spots or streaks on leaves and stems followed by stunting and death of plants. Morphological and host range analyses of extracts from infected plants suggested that the causal agent of disease was a Broad bean wilt virus (BBWV), and the virus was tentatively named a Korean isolate of BBWV (BBWV-K). When the isolate was back-inoculated onto hot pepper plants, it induced symptoms similar to those of naturally infected hot pepper in the field. Two coat proteins (CPs) of 44 and 22 kDa, corresponding to a large CP and a small CP, respectively, were identified from the virus, and both reacted specifically with polyclonal antibody to BBWV 2. The complete nucleotide sequences of RNA 1 and RNA 2 of the isolate were determined from cDNA clones. The deduced amino acid sequence data from the putative proteins encoded by RNA 1 and 2 of the BBWV-K indicated a closer relationship with the isolates of BBWV 2 than BBWV 1. However, sequence comparison of the 5' noncoding regions of the viruses differentiates BBWV-K from other BBWV 2 isolates. Another distinctive feature of the BBWV-K is that it generates defective RNAs in hot pepper exhibiting necrotic symptoms, which is the first report of defective RNAs in the Fabavirus genera of BBWVs.
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Matsumoto G, Omi Y, Lee U, Nishimura T, Shindo J, Penninger JM. Adhesion mediated by LFA-1 is required for efficient IL-12-induced NK and NKT cell cytotoxicity. Eur J Immunol 2000; 30:3723-31. [PMID: 11169416 DOI: 10.1002/1521-4141(200012)30:12<3723::aid-immu3723>3.0.co;2-9] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Interleukin 12 (IL-12)-activated NK1.1+TCRalpha beta+ (NKT2) and NK1.1+TCRalpha beta- (NK) cells exhibit cytotoxic activity against a wide variety of tumor cells in the absence of prior sensitization. Here we demonstrate that the integrin adhesion receptor LFA-1 (CD11a/CD18) regulates the cytotoxic activity of IL-12-activated NKT and NK cells against YAC-1 and EL-4 tumor cells. Differentiation in vivo and the expression of the cytolytic effector molecules perforin and Fas-L were comparable in both IL-12-activated NKT and NK cells from LFA-1-/ - and LFA-1+/+ mice. However, LFA-1-/-IL-12-activated NKT and NK cells showed impaired conjugate formation with target cells. These results provide the first genetic evidence for a role for an adhesion receptor in killing by IL-12-activated NK cells.
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MESH Headings
- Animals
- Antigens/analysis
- Antigens, Ly
- Antigens, Surface
- Cell Adhesion
- Cytotoxicity, Immunologic
- Fas Ligand Protein
- Interleukin-12/pharmacology
- Killer Cells, Natural/immunology
- Killer Cells, Natural/physiology
- Lectins, C-Type
- Lymphocyte Function-Associated Antigen-1/physiology
- Membrane Glycoproteins/analysis
- Mice
- Mice, Inbred C57BL
- NK Cell Lectin-Like Receptor Subfamily B
- Perforin
- Pore Forming Cytotoxic Proteins
- Proteins/analysis
- Receptors, Antigen, T-Cell, alpha-beta/analysis
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Lee U, Bastos AC, Alonso-Vanegas MA, Morris R, Olivier A. Topographic analysis of the gyral patterns of the central area. Stereotact Funct Neurosurg 2000; 70:38-51. [PMID: 9691240 DOI: 10.1159/000029597] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Great advances in imaging technology allows the surgeon to visualize the entire brain surface during surgery. However, the cerebral convolutions are extremely complex, so that it is often difficult to define the central area precisely. Using the curvilinear reconstruction technique (Gyroview) and MRI, we have analyzed the gyral anatomy of the central area in 20 normal brans and have recognized several patterns of topographic organization and have classified them into several categories. We divided the central area into anterior and posterior subregions with the central sulcus as the main landmark. More specifically, we studied how the pre- and postcentral gyri merge into the frontal and parietal lobe proper by anatomical bridges (roots). We describe three anterior and two main posterior roots which originate from the precentral and the postcentral gyrus, respectively. We found four different types of pattern for the anterior roots and as many as 10 different patterns for the posterior roots. The arterior roots are relatively constant, compared to the posterior ones. The most frequent pattern (type 1) was found in 33 hemispheres among the 40 analyzed (82.5%). Four main posterior root patterns were recognized in 32 hemispheres of the 40 analyzed (80%). Thus, although gyral variability was encountered for the posterior roots, a very constant global pattern was seen for the central area. One of the most important steps of frameless stereotactic-guided epilepsy surgery is the precise localization of the central area. Therefore, a knowledge of gyral patterns of the central area is essential not only for the resective epilepsy surgery, but also for the successful removal of a variety of lesions in the central area.
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Terheyden H, Lee U, Ludwig K, Kreusch T, Hedderich J. Sterilization of elastic ligatures for intraoperative mandibulomaxillary immobilization. Br J Oral Maxillofac Surg 2000; 38:299-304. [PMID: 10922155 DOI: 10.1054/bjom.1999.0237] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Sterilization can influence the mechanical properties of elastic ligatures used for mandibulomaxillary immobilization. The aim of this study was to compare different sterilization protocols (ethylene oxide, autoclave, irradiation, plasma sterilization, povidone-iodine for 24 hours and 70% isopropyl alcohol for 24 hours) of three elastomers (natural rubber, silicone rubber, and polyurethane). Three mechanical variables were assessed in a testing machine: breaking strength, tensile strength and tensile strength after a 24-hour load (material fatigue). Natural rubber was most susceptible to mechanical alteration by sterilization and lost 46% of its breaking strength and 43% of its tensile strength after autoclaving. Polyurethane was more resistant (multiple comparison, Tukey-Kramer), but polyurethane ligatures stuck together after autoclaving. The protocols for low-temperature sterilization, ethylene oxide, irradiation, and plasma were superior to autoclaving and the disinfecting solutions. These data suggest that polyurethane sterilized with ethylene oxide is the material of choice.
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Lee KC, Park HK, Mo KS, Chang YJ, Cho YL, Lee U. Propofol Anesthesia in Stereotactic Operation for Movement Disorders. Korean J Anesthesiol 1998. [DOI: 10.4097/kjae.1998.35.1.64] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Jiang G, Lee U, Sladek FM. Proposed mechanism for the stabilization of nuclear receptor DNA binding via protein dimerization. Mol Cell Biol 1997; 17:6546-54. [PMID: 9343418 PMCID: PMC232508 DOI: 10.1128/mcb.17.11.6546] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Hepatocyte nuclear factor 4 (HNF-4) defines a new subgroup of nuclear receptors that exist in solution and bind DNA exclusively as homodimers. We recently showed that the putative ligand binding domain (LBD) of HNF-4 is responsible for dimerization in solution and prevents heterodimerization with other receptors. In this report, the role of the LBD in DNA binding by HNF-4 is further investigated by using electrophoretic mobility shift analysis. A comparison of constructs containing either the DNA binding domain (DBD) alone or the DBD plus the LBD of HNF-4 showed that dimerization via the DBD was sufficient to provide nearly the full DNA binding affinity of the full-length HNF-4. In contrast, dimerization via the DBD was not sufficient to produce a stable protein-DNA complex, whereas dimerization via the LBD increased the half-life of the complex by at least 100-fold. Circular permutation analysis showed that full-length HNF-4 bent DNA by approximately 80 degrees while the DBD bent DNA by only 24 degrees. Nonetheless, analysis of other constructs indicated that the increase in stability afforded by the LBD could be explained only partially by an increased ability to bend DNA. Coimmunoprecipitation studies, on the other hand, showed that dimerization via the LBD produced a protein-protein complex that was much more stable than the corresponding protein-DNA complex. These results led us to propose a model in which dimerization via the LBD stabilizes the receptor on DNA by converting an energetically favorable two-step dissociation event into an energetically unfavorable single-step event. Implications of this one-step model for other nuclear receptors are discussed.
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Choi G, Lee U, Kim A, Choi JO. Castleman's disease of the parotid gland. THE JOURNAL OF OTOLARYNGOLOGY 1997; 26:319-21. [PMID: 9343770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Lim PO, Ryu JS, Lee HJ, Lee U, Park YS, Kwak JM, Choi JK, Nam HG. Resistance to tobamoviruses in transgenic tobacco plants expressing the coat protein gene of pepper mild mottle virus (Korean isolate). Mol Cells 1997; 7:313-9. [PMID: 9264016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Red pepper, one of the most important vegetable crops in Korea, is severely affected by viral diseases causing 20-50% reduction in product yield. A pepper strain of tobacco mosaic virus (TMV-p) is the most common virus in red pepper. To study the molecular structure of the TMV-p virus, we generated cDNA clones of the viral genome. Partial sequencing of a few cDNA clones revealed that TMV-p shares a 98% identity at the nucleotide level with the Spanish isolate of pepper mild mottle virus (PMMV-s). This suggests that TMV-p should be reclassified as the Korean isolate of PMMV (PMMV-k). The coat protein (CP) gene together with the 3' untranslated region of the PMMV-k virus was obtained by reverse transcriptase-polymerase chain reaction (RT-PCR) using oligomers deduced from the sequence of PMMV-s. The sequence analysis of the CP gene and the 3' untranslated region further confirmed that PMMV-k is highly related to PMMV-s. The CP gene and the 3' untranslated region of PMMV-k were cloned into a plant expression vector and the construct was introduced into tobacco plants. The transgenic plants expressing the PMMV-k CP gene were delayed in developing systemic disease or failed to develop symptoms at all after inoculation with PMMV-k. Delay of symptoms was also observed when the plants were inoculated with TMV-OM which shares a 74% homology with PMMV-k in the amino acid sequence of the CP region. In a local lesion host, the CP expressing plants exhibited a greatly reduced number of necrotic lesions as compared to control plants after inoculation with TMV-OM. Our results show that CP-mediated viral resistance is readily applicable in the case of PMMV-k and can provide resistance to other viruses in the tobamovirus group.
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Abstract
BACKGROUND Fibrous histiocytoma is a slow-growing tumor that most commonly occurs in the superficial and deep soft tissue, with an occasional occurrence in the orbit. However, fibrous histiocytoma of the lacrimal sac is very rare. METHODS A case report of a 33-year-old man with a palpable mass in the right lacrimal sac and epiphora is presented, with a review of the literature pertaining to this unusual case. RESULTS The patient was found to have a 3 x 2-cm-sized mass in the right lacrimal sac. Under the impression of benign tumor, the tumor was excised. Histopathological diagnosis of fibrous histiocytoma was made on the surgical specimen. Following surgical treatment, the patient has remained free of symptoms. CONCLUSIONS Fibrous histiocytoma of the lacrimal sac is a rare disease. This case report and a review of the literature demonstrated that surgical excision appears to control the tumor.
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Hirata K, Lee U, Sakurai Y, Sasakura Y, Sindo J. Study of the susceptibility of anti-tumor drug resistant cells to IL-1 induced LAK cells. Int J Oral Maxillofac Surg 1997. [DOI: 10.1016/s0901-5027(97)81390-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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