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Lee S, Yoo JH, Lee SW. Kikuchi disease: differentiation from tuberculous lymphadenitis based on patterns of nodal necrosis on CT. AJNR Am J Neuroradiol 2011; 33:135-40. [PMID: 22173774 DOI: 10.3174/ajnr.a2724] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE KD, also known as histiocytic necrotizing lymphadenitis, is often mimicked by TL, especially when KD is accompanied by gross necrosis on CT. We analyzed the nodal necrosis patterns on CT in patients with KD and TL to identify the predictive features that differentiate these 2 entities. MATERIALS AND METHODS We included 24 patients with KD (14 females, 10 males; mean age, 25.1 years) and 45 with TL (36 women, 9 men; mean age, 39.9 years) having nodal necrosis on CT. The extent, number, location, and margins of nodal necrosis; the presence of perinodal infiltration; and nodal calcification were analyzed. Two attenuation indices for nodal necrosis were derived: CTN and CTN/M. The CT features of the 2 diseases were compared, and multivariate logistic regression analysis was performed to identify predictive features that would aid in differentiating KD from TL. RESULTS Mild or moderate extent of nodal necrosis (P = .000), multiple necrotic foci (P = .002), indistinct margins of necrotic foci (P = .000), CTN of >44.5 (P = .000), CTN/M of >0.7 (P = .000), and absence of nodal calcification (P = .012) were associated with KD. Multivariate logistic regression analysis revealed that indistinct margins of necrotic foci were independent predictors, with 80% accuracy. CONCLUSIONS The presence of indistinct margins of necrotic foci was an independent predictor in differentiating KD from TL with high diagnostic accuracy.
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Kim J, Song J, Lyu CJ, Kim YR, Oh SH, Choi YC, Yoo JH, Choi JR, Kim H, Lee KA. Population-specific spectrum of the F11 mutations in Koreans: evidence for a founder effect. Clin Genet 2011; 82:180-6. [DOI: 10.1111/j.1399-0004.2011.01732.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Chung KW, Suh BC, Cho SY, Choi SK, Kang SH, Yoo JH, Hwang JY, Choi BO. Early-onset Charcot-Marie-Tooth patients with mitofusin 2 mutations and brain involvement. J Neurol Neurosurg Psychiatry 2010; 81:1203-6. [PMID: 20587496 DOI: 10.1136/jnnp.2009.181669] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Mutations of the mitofusin 2 (MFN2) gene have been reported to be the most common cause of the axonal form of Charcot-Marie-Tooth disease (CMT). A prospective brain MRI study was performed on 18 early-onset CMT patients with MFN2 mutations, and a high frequency (39%) of brain abnormalities was found. Early-onset patients showed multiple scattered or confluent brain lesions that involved gray matter as well as white matter. Patterns of brain involvement in early-onset patients differed from those of late-onset patients and other hereditary peripheral neuropathies. In addition, one CMT patient demonstrated a brain lesion before the development of peripheral neuropathy.
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Tanaka EY, Yoo JH, Rodrigues AJ, Utiyama EM, Birolini D, Rasslan S. A computerized tomography scan method for calculating the hernia sac and abdominal cavity volume in complex large incisional hernia with loss of domain. Hernia 2009; 14:63-9. [PMID: 19756913 DOI: 10.1007/s10029-009-0560-8] [Citation(s) in RCA: 121] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2009] [Accepted: 08/25/2009] [Indexed: 11/24/2022]
Abstract
Preoperative progressive pneumoperitoneum (PPP) is a safe and effective procedure in the treatment of large incisional hernia (size > 10 cm in width or length) with loss of domain (LIHLD). There is no consensus in the literature on the amount of gas that must be insufflated in a PPP program or even how long it should be maintained. We describe a technique for calculating the hernia sac volume (HSV) and abdominal cavity volume (ACV) based on abdominal computerized tomography (ACT) scanning that eliminates the need for subjective criteria for inclusion in a PPP program and shows the amount of gas that must be insufflated into the abdominal cavity in the PPP program. Our technique is indicated for all patients with large or recurrent incisional hernias evaluated by a senior surgeon with suspected LIHLD. We reviewed our experience from 2001 to 2008 of 23 consecutive hernia surgical procedures of LIHLD undergoing preoperative evaluation with CT scanning and PPP. An ACT was required in all patients with suspected LIHLD in order to determine HSV and ACV. The PPP was performed only if the volume ratio HSV/ACV (VR = HSV/ACV) was >or=25% (VR >or= 25%). We have performed this procedure on 23 patients, with a mean age of 55.6 years (range 31-83). There were 16 women and 7 men with an average age of 55.6 years (range 31-83), and a mean BMI of 38.5 kg/m(2) (range 23-55.2). Almost all patients (21 of 23 patients-91.30%) were overweight; 43.5% (10 patients) were severely obese (obese class III). The mean calculated volumes for ACV and HSV were 9,410 ml (range 6,060-19,230 ml) and 4,500 ml (range 1,850-6,600 ml), respectively. The PPP is performed by permanent catheter placed in a minor surgical procedure. The total amount of CO(2) insufflated ranged from 2,000 to 7,000 ml (mean 4,000 ml). Patients required a mean of 10 PPP sessions (range 4-18) to achieve the desired volume of gas (that is the same volume that was calculated for the hernia sac). Since PPP sessions were performed once a day, 4-18 days were needed for preoperative preparation with PPP. The mean VR was 36% (ranged from 26 to 73%). We conclude that ACT provides objective data for volume calculation of both hernia sac and abdominal cavity and also for estimation of the volume of gas that should be insufflated into the abdominal cavity in PPP.
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Bailey A, Metaxas A, Yoo JH, McGee T, Kitchen I. Decrease of D2 receptor binding but increase in D2-stimulated G-protein activation, dopamine transporter binding and behavioural sensitization in brains of mice treated with a chronic escalating dose 'binge' cocaine administration paradigm. Eur J Neurosci 2008; 28:759-70. [PMID: 18671743 DOI: 10.1111/j.1460-9568.2008.06369.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Understanding the neurobiology of the transition from initial drug use to excessive drug use has been a challenge in drug addiction. We examined the effect of chronic 'binge' escalating dose cocaine administration, which mimics human compulsive drug use, on behavioural responses and the dopaminergic system of mice and compared it with a chronic steady dose (3 x 15 mg/kg/day) 'binge' cocaine administration paradigm. Male C57BL/6J mice were injected with saline or cocaine in an escalating dose paradigm for 14 days. Locomotor and stereotypy activity were measured and quantitative autoradiographic mapping of D(1) and D(2) receptors, dopamine transporters and D(2)-stimulated [(35)S]GTPgammaS binding was performed in the brains of mice treated with this escalating and steady dose paradigm. An initial sensitization to the locomotor effects of cocaine followed by a dose-dependent increase in the duration of the locomotor effect of cocaine was observed in the escalating but not the steady dose paradigm. Sensitization to the stereotypy effect of cocaine and an increase in cocaine-induced stereotypy score was observed from 3 x 20 to 3 x 25 mg/kg/day cocaine. There was a significant decrease in D(2) receptor density, but an increase in D(2)-stimulated G-protein activity and dopamine transporter density in the striatum of cocaine-treated mice, which was not observed in our steady dose paradigm. Our results document that chronic 'binge' escalating dose cocaine treatment triggers profound behavioural and neurochemical changes in the dopaminergic system, which might underlie the transition from drug use to compulsive drug use associated with addiction, which is a process of escalation.
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Chung KW, Suh BC, Shy ME, Cho SY, Yoo JH, Park SW, Moon H, Park KD, Choi KG, Kim S, Kim SB, Shim DS, Kim SM, Sunwoo IN, Choi BO. Different clinical and magnetic resonance imaging features between Charcot-Marie-Tooth disease type 1A and 2A. Neuromuscul Disord 2008; 18:610-8. [PMID: 18602827 DOI: 10.1016/j.nmd.2008.05.012] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2007] [Revised: 05/23/2008] [Accepted: 05/28/2008] [Indexed: 01/01/2023]
Abstract
Charcot-Marie-Tooth disease type 1A (CMT1A) is the more frequent cause of demyelinating CMT, and CMT2A is the most common cause of axonal CMT. We conducted a magnetic resonance imaging (MRI) study on 39 CMT1A and 21 CMT2A patients to compare their neuroimaging patterns and correlate with clinical features. CMT1A patients showed selective fatty infiltration with a preference for anterior and lateral compartment muscles, whereas CMT2A patients showed a preference for superficial posterior compartment muscles. Early-onset CMT2A patients showed more severe leg fatty atrophy than late-onset CMT2A patients. In late-onset CMT2A, soleus muscle was the earliest, and most severely affected than the other leg muscles. Selective involvement of intrinsic foot muscles is a characteristic pattern of minimal CMT1A and CMT2A. Our MRI study demonstrates different patterns of fatty infiltration involving superficial posterior compartment muscles in CMT2A (partial T-type), and peroneal nerve innervated muscles in CMT1A (P-type).
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Chung KW, Cho SY, Hwang SJ, Kim KH, Yoo JH, Kwon O, Kim SM, Sunwoo IN, Züchner S, Choi BO. Early-onset stroke associated with a mutation in mitofusin 2. Neurology 2008; 70:2010-1. [PMID: 18490623 DOI: 10.1212/01.wnl.0000312513.96457.7a] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Yoo JH, Kang YG, Chang CB, Seong SC, Kim TK. The relationship of the medially-offset stem of the tibial component to the medial tibial cortex in total knee replacements in Korean patients. ACTA ACUST UNITED AC 2008; 90:31-6. [PMID: 18160496 DOI: 10.1302/0301-620x.90b1.19605] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We examined the placement of the stem in relation to the medial tibial cortex when using total knee replacements (TKRs) with medially-offset tibial stems in Korean patients. Measurements were performed on the pre- and post-operative radiographs of 246 osteoarthritic knees replaced between January 2005 and May 2006 using the Genesis II or E-motion TKR with a medially-offset stem. Pre-operatively, we measured the distance between the mechanical axis and that of the tibial shaft and post-operatively, that between the midline of the tibial stem and the axis of the shaft. Knees were identified in which there was radiological contact between the tip of the stem and the medial tibial cortex. The mechanical axis was located medial to the axis of the shaft in 203 knees (82.5%). Post-operatively, the midline of the tibial stem was located medial to the tibial shaft axis in 196 knees (79.7%). In 16 knees (6.5%) there was radiological contact between the tibial stem or cement mantle and the medial tibial cortex. Our study has shown that the medially-offset stem in the tibial component may not be a good option for knees undergoing replacement for advanced osteoarthritis in some Korean patients.
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Shin JC, Chang WH, Jung TH, Yoo JH, Park SN. The determination of sensation-dependent bladder emptying time in patients with complete spinal cord injury above T11. Spinal Cord 2007; 46:210-5. [PMID: 17646839 DOI: 10.1038/sj.sc.3102102] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
STUDY DESIGN Retrospective investigation using urodynamic studies and medical records. OBJECTIVE To evaluate the safety of sensation-dependent bladder emptying in complete spinal cord injury (SCI) patients, based on the preservation of the desire to void. SETTING Spinal Cord Injury Unit, Yonsei Rehabilitation Hospital, Seoul, Korea. METHODS This study was performed retrospectively on 79 complete SCI patients with lesions above T11, who had preserved the desire to void during conventional urodynamic studies. Patients were classified according to detrusor compliance and maximal bladder capacity. The clinical and urodynamic characteristics of each group were analyzed. RESULTS Forty-five (57.0%) patients were classified as group A and 34 (43.0%) patients were classified as group B. There were no significant differences in clinical features, such as voiding methods and the presence of autonomic dysreflexia between the two groups. Compared with group B, there were significantly more areflexic neurogenic bladder cases in group A (P<0.05). There were significantly higher maximal detrusor pressures in group B (P<0.05). There were significantly more cases with the preservation of the strong desire to void in group B (P<0.05). CONCLUSION Not all patients with discomplete SCIs accepted the use of sensation-dependent bladder emptying. The safe use of sensation-dependent bladder emptying will be determined based on the results of urodynamic studies.
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Bailey A, Yoo JH, Racz I, Zimmer A, Kitchen I. Preprodynorphin mediates locomotion and D2 dopamine and mu-opioid receptor changes induced by chronic 'binge' cocaine administration. J Neurochem 2007; 102:1817-1830. [PMID: 17532787 DOI: 10.1111/j.1471-4159.2007.04661.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Evidence suggests that the kappa-opioid receptor (KOP-r) system plays an important role in cocaine addiction. Indeed, cocaine induces endogenous KOP activity, which is a mechanism that opposes alterations in behaviour and brain function resulting from repeated cocaine use. In this study, we have examined the influence of deletion of preprodynorphin (ppDYN) on cocaine-induced behavioural effects and on hypothalamic-pituitary-adrenal axis activity. Furthermore, we have measured mu-opioid receptor (MOP-r) agonist-stimulated [(35)S]GTPgammaS, dopamine D(1), D(2) receptor and dopamine transporter (DAT) binding. Male wild-type (WT) and ppDYN knockout (KO) mice were injected with saline or cocaine (45 mg/kg/day) in a 'binge' administration paradigm for 14 days. Chronic cocaine produced an enhancement of locomotor sensitisation in KO. No genotype effect was found on stereotypy behaviour. Cocaine-enhanced MOP-r activation in WT but not in KO. There was an overall decrease in D(2) receptor binding in cocaine-treated KO but not in WT mice. No changes were observed in D(1) and DAT binding. Cocaine increased plasma corticosterone levels in WT but not in KO. The data confirms that the endogenous KOP system inhibits dopamine neurotransmission and that ppDYN may mediate the enhancement of MOP-r activity and the activation of the hypothalamic-pituitary-adrenal axis after chronic cocaine treatment.
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MESH Headings
- Analgesics, Opioid/metabolism
- Analgesics, Opioid/pharmacology
- Animals
- Binding, Competitive/drug effects
- Binding, Competitive/physiology
- Cocaine/adverse effects
- Cocaine-Related Disorders/genetics
- Cocaine-Related Disorders/metabolism
- Cocaine-Related Disorders/physiopathology
- Corticosterone/metabolism
- Dopamine Plasma Membrane Transport Proteins/drug effects
- Dopamine Plasma Membrane Transport Proteins/metabolism
- Dopamine Uptake Inhibitors/adverse effects
- Drug Administration Schedule
- Dynorphins/genetics
- Dynorphins/metabolism
- Guanosine 5'-O-(3-Thiotriphosphate)/metabolism
- Hypothalamo-Hypophyseal System/drug effects
- Hypothalamo-Hypophyseal System/metabolism
- Hypothalamo-Hypophyseal System/physiopathology
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Motor Activity/drug effects
- Motor Activity/physiology
- Pituitary-Adrenal System/drug effects
- Pituitary-Adrenal System/physiology
- Protein Precursors/genetics
- Protein Precursors/metabolism
- Receptors, Dopamine D1/drug effects
- Receptors, Dopamine D1/metabolism
- Receptors, Dopamine D2/drug effects
- Receptors, Dopamine D2/metabolism
- Receptors, Opioid, kappa/drug effects
- Receptors, Opioid, kappa/metabolism
- Receptors, Opioid, mu/drug effects
- Receptors, Opioid, mu/metabolism
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Jang I, Moon JH, Yoon JB, Yoo JH, Yang TJ, Kim YJ, Park HG. Application of RAPD and SCAR markers for purity testing of F1 hybrid seed in chili pepper (Capsicum annuum). Mol Cells 2004; 18:295-9. [PMID: 15650324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2023] Open
Abstract
A simpler and better method for purity testing of hybrid pepper seed was developed. The simplest method for extracting genomic DNA, the NaOH method, was chosen. Two RAPD markers identifying male and female parents were also developed, and the PCR products of male- and female-specific RAPD markers were cloned and sequenced. From these sequences, new longer primers were constructed for conversion into SCAR markers. In blind tests the RAPD and SCAR markers were able to reliably detect contaminating exotic seeds. These PCR-based markers are therefore directly applicable for purity testing by seed companies. In addition, the PCR products of the SCAR markers could be identified by direct staining methods such as ethidium bromide and pellet painting without electrophoresis.
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Yoo JH, Murakami Y, Shindo D, Atou T, Kikuchi M. Interaction of separated ferromagnetic domains in a hole-doped manganite achieved by a magnetic field. PHYSICAL REVIEW LETTERS 2004; 93:047204. [PMID: 15323790 DOI: 10.1103/physrevlett.93.047204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2004] [Indexed: 05/24/2023]
Abstract
We report the change in the magnetic microstructure with the application of a magnetic field to a hole-doped manganite La0.81Sr0.19MnO3 in the mixed-phase state, in which ferromagnetic and paramagnetic phases coexist. In situ observations by electron holography have revealed that the applied magnetic field generates a "channel" of the magnetic flux in the paramagnetic phase region, thereby connecting the separated ferromagnetic domains. The magnetic flux density of this channel is estimated at 0.33 T, which is comparable with that of the ferromagnetic domains. The connection of the separated ferromagnetic domains appears to promote the conduction in the mixed-phase state as predicted for many manganites exhibiting the magnetoresistance effect.
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Poddar P, Wilson JL, Srikanth H, Yoo JH, Wereley NM, Kotha S, Barghouty L, Radhakrishnan R. Nanocomposite magneto-rheological fluids with uniformly dispersed Fe nanoparticles. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2004; 4:192-196. [PMID: 15112566 DOI: 10.1166/jnn.2004.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A systematic study of the magnetic and rheological properties of magneto-rheological (MR) fluids containing micron-size and nano-size iron particles is presented. The MR fluids were prepared with hydraulic oil as the carrier liquid and lecithin as an effective surfactant medium that promotes uniform particle dispersion. Magnetic measurements on micron-, hybrid-(nano + micron), and nano-MR fluids clearly indicate that the partial replacement of the micro-size particles by nanoparticles results in a better suspension and robust chain formation under applied external magnetic fields. For nano-MR fluids, the measured yield stress was found to be lower than micron-MR fluids. However, better flow properties and sharper magnetic switching make nanoparticle-based MR fluids appealing for microfluidics device applications where higher yield stress is not required.
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Choi BH, Huh JY, Yoo JH. Computed tomographic findings of the fractured mandibular condyle after open reduction. Int J Oral Maxillofac Surg 2003; 32:469-73. [PMID: 14759103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
The purpose of this study was to evaluate the long-term radiological results obtained with open reduction and fixation of unilateral mandibular condyle fractures in 10 patients. CT images taken at the end of the follow-up period (average of 22 months, range 7 to 33 months), were traced and digitized, and the position and morphology of the fractured condylar process was statistically compared with those of the contralateral non-fractured condylar process in the coronal, transverse and sagittal planes. Little difference was observed in the position or morphology of the condylar process in the operated and non-fractured joints. This study shows that it is possible to anatomically reduce fractured condyles, and thereby to avoid postoperative disadvantageous joint changes.
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Murakami Y, Yoo JH, Shindo D, Atou T, Kikuchi M. Magnetization distribution in the mixed-phase state of hole-doped manganites. Nature 2003; 423:965-8. [PMID: 12827195 DOI: 10.1038/nature01715] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2003] [Accepted: 04/29/2003] [Indexed: 11/09/2022]
Abstract
The effect of 'colossal magnetoresistance' (CMR) in hole-doped manganites--an abnormal decrease of resistivity when a magnetic field is applied--has attracted significant interest from researchers in the past decade. But the underlying mechanism for the CMR phenomenon is not yet fully understood. It has become clear that a phase-separated state, where magnetic and non-magnetic phases coexist, is important, but the detailed magnetic microstructure of this mixed-phase state is so far unclear. Here we use electron microscopy to study the magnetic microstructure and development of ferromagnetic domains in the mixed-phase state of La(1-x)Sr(x)MnO3 (x = 0.54, 0.56). Our measurements show that, in the absence of a magnetic field, the magnetic flux is closed within ferromagnetic regions, indicating a negligible magnetic interaction between separated ferromagnetic domains. However, we also find that the domains start to combine with only very small changes in temperature. We propose that the delicate nature of the magnetic microstructure in the mixed-phase state of hole-doped manganites is responsible for the CMR effect, in which significant conduction paths form between the ferromagnetic domains upon application of a magnetic field.
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Choi SM, Lee DG, Kim MS, Park YH, Kim YJ, Lee S, Kim HJ, Choi JH, Yoo JH, Kim DW, Min WS, Shin WS, Kim CC. Bacteremic cellulitis caused by non-O1, non-O139 Vibrio cholerae in a patient following hematopoietic stem cell transplantation. Bone Marrow Transplant 2003; 31:1181-2. [PMID: 12796802 DOI: 10.1038/sj.bmt.1704044] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Yoo JH, Lee CT, Shim YS, Chung JW, Ahn H, Kim KW. Aortobronchial fistula presenting as recurrent hemoptysis and successfully treated with an endovascular stent graft. Respiration 2002; 68:537-9. [PMID: 11694820 DOI: 10.1159/000050565] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Aortobronchial fistula (ABF) (aortopulmonary fistula) may cause a massive fatal hemoptysis. We have recently seen a patient with ABF presenting with recurrent, massive hemoptysis. She was successfully treated with an endovascular stent graft. The endovascular stent graft may provide an alternative treatment of in patients considered to be poor surgical candidates.
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Yoo JH, Cheng OH, Gerber GE. Determination of the native form of FadD, the Escherichia coli fatty acyl-CoA synthetase, and characterization of limited proteolysis by outer membrane protease OmpT. Biochem J 2001; 360:699-706. [PMID: 11736662 PMCID: PMC1222275 DOI: 10.1042/0264-6021:3600699] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Several studies have described FadD, the Escherichia coli fatty acyl-CoA synthetase [also known as fatty acid:CoA ligase (AMP-forming); EC 6.2.1.3], as a 42-50 kDa enzyme. Based on sequencing and expression data from the fadD gene, other reports have suggested that FadD is a 62 kDa protein and represents the sole fatty acyl-CoA synthetase in E. coli. We report that the 62 kDa FadD enzyme is a substrate for the outer membrane protease OmpT in vitro, producing a 43 kDa C-terminal fragment and a 19 kDa N-terminal fragment. Immunoblotting with a FadD antibody revealed that only the 62 kDa form of the enzyme is present in vivo, but we utilized the proteolytic sensitivity of FadD to investigate its structure. Photoaffinity labelling experiments revealed that both intact FadD and the 43 kDa fragment bound a long-chain fatty acid. Intact and cleaved FadD were also purified to determine the effect of cleavage on function. When using oleate as a substrate, cleaved FadD displayed 2-fold higher K(m) and V(max) values compared with intact FadD, but the catalytic efficiencies (k(cat)/K(m)) of the two forms were similar. This indicated that cleavage did not adversely affect enzyme activity. Proteolysis of FadD by OmpT was altered by the presence of oleate or ATP, both of which are ligands for the fatty acyl-CoA synthetase. This suggested that FadD undergoes ligand-induced conformational changes and implies that the region surrounding the cleavage site is mobile, a common characteristic of linker domains.
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Choi BH, Suh CH, Par JH, Yoo JH, Kim HJ. An effective technique for open reduction of mandibular angle fractures using new reduction forceps: technical innovations. Int J Oral Maxillofac Surg 2001; 30:555-7. [PMID: 11829240 DOI: 10.1054/ijom.2001.0158] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
We demonstrate a new technique that is useful for precompressing and holding mandibular angle fractures by means of new reduction forceps. The forceps were designed for application in the mandibular angle area via a transoral approach.
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Kim YK, Yoo JH, Woo JS, Jung JS, Kim BS, Kim SY. Effect of pentoxifylline on ischemic acute renal failure in rabbits. Ren Fail 2001; 23:757-72. [PMID: 11777315 DOI: 10.1081/jdi-100108187] [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: 11/03/2022] Open
Abstract
Previous studies have demonstrated that levels of tumor necrosis factor-alpha (TNF-alpha) or its mRNA expression are increased in acute renal failure of various types including ischemia/reperfusion injury. This study was undertaken to determine whether pentoxifylline (PTX), an inhibitor of TNF-alpha production, provides a protective effect against ischemic acute renal failure in rabbits. Renal ischemia was induced by clamping bilateral renal arteries for 60 min. Animals were pretreated with PTX (30 mg/kg, i.v.) 10 min before release of clamp. At 24 h of reperfusion of blood after ischemia, changes in renal function, renal blood flow, and the expression of TNF-alpha mRNA were evaluated. Ischemia/reperfusion caused a marked reduction in GFR, which was accompanied by an increase of serum creatinine levels. Such changes were significantly attenuated by PTX pretreatment. PTX ameliorated the impairment of renal tubular function, but it had no effect on the reduction of renal blood flow induced by ischemia/reperfusion. The protective effect of PTX on functional changes was supported by morphological studies. The impairment of glucose and phosphate reabsorption in postischemic kidneys was associated with a depression in the expression of Na+-glucose and Na+-Pi transporters. The expression of TNF-alpha mRNA was increased after reperfusion, which was inhibited by PTX pretreatment. The PTX pretreatment in vitro prevented the release of lactate dehydrogenase induced by an oxidant t-butylhydroperoxide in rabbit renal cortical slices, but it did not produce any effect on the oxidant-induced lipid peroxidation, suggesting that PTX protection is not resulted from its antioxidant action. These results suggest that PTX may exert a protective effect against ischemic acute renal failure by inhibiting the production of TNF-alpha in rabbits.
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Kim JC, Jeong JC, Park HC, Yoo JH, Koo YD, Yoon HW, Koo SC, Lee SH, Bahk JD, Cho MJ. Cold accumulation of SCOF-1 transcripts is associated with transcriptional activation and mRNA stability. Mol Cells 2001; 12:204-8. [PMID: 11710522] [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
Cold acclimation enhances the transcription of several cold regulated (COR) genes. However, little is known about whether the elevation of the transcriptional level of the COR genes is due to transcriptional activation, or mRNA stability by a low temperature. Recently, we cloned a novel cold-inducible zinc finger protein gene from soybean, SCOF-1, which may function as a positive regulator of the COR gene expression . Here we report that the elevation of the SCOF-1 transcript level by cold stress is associated with both transcriptional activation and post-transcriptional mRNA stability under a low temperature. A nuclear run-on assay reveals that cold acclimation elevates the SCOF-1 transcript about three-fold compared to that of non-acclimated soybean nuclei. Furthermore, SCOF-1 transcripts increased substantially by a low temperature in transgenic tobacco plants that constitutively expressed SCOF-1 under the control of a constitutive cauliflower mosaic virus (CaMV) 35S promoter. When a transcription inhibitor, cordycepin, was treated with the deacclimating soybean cell, the decay level of the SCOF-1 transcripts was delayed significantly. This suggests that it may affect de novo protein synthesis, which degrades the SCOF-1 mRNA at room temperature. In addition, a secondary structure may be involved in the mRNA stability of SCOF-1 under a low temperature.
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Yoo JH, Lee SC. Elevated levels of plasma homocyst(e)ine and asymmetric dimethylarginine in elderly patients with stroke. Atherosclerosis 2001; 158:425-30. [PMID: 11583722 DOI: 10.1016/s0021-9150(01)00444-0] [Citation(s) in RCA: 148] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Cerebrovascular risk factors, including hypertension, smoking, diabetes mellitus, aging, dyslipidemia, and hyperhomocyst(e)inemia are linked to endothelial dysfunction. Endothelial-derived nitric oxide (NO) has inhibitory effects on key processes in atherothrombosis. Although asymmetric dimethylarginine (ADMA), an endogenous inhibitor of NO synthase, is associated with atherosclerotic disease, there has been no report on association of ADMA with ischemic stroke. Here we investigated the relation of plasma ADMA, stroke, and homocyst(e)inemia in the elderly. Plasma ADMA and homocyst(e)ine concentration was determined using high-performance liquid chromatography and fluorescence detection. Patients with ischemic stroke had significantly higher concentrations of plasma ADMA than controls (1.85+/-1.32 vs. 0.93+/-0.32 micromol/l, P=0.0001). After adjustment for risk factors, elevated ADMA levels, above 90th percentile of normal controls (> or =1.43 micromol/l) was associated with stroke (OR=6.05, 95% CI; 2.77-13.3, P=0.02). ADMA plasma levels were positively correlated to homocyst(e)ine levels (r=0.43, P=0.01). Multiple logistic regression analysis revealed that hyperhomocyst(e)inemia (plasma homocyst(e)ine concentration > or =15.0 micromol/l) was a significant predictor of elevated ADMA level. Altogether, findings indicate that elevated ADMA concentrations are at increased risk for ischemic stroke in the elderly, and may account for increased risk of stroke in patients with hyperhomocyst(e)inemia.
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Lee CS, Lee CK, Kim YT, Hong YM, Yoo JH. Dynamic sagittal imbalance of the spine in degenerative flat back: significance of pelvic tilt in surgical treatment. Spine (Phila Pa 1976) 2001; 26:2029-35. [PMID: 11547204 DOI: 10.1097/00007632-200109150-00017] [Citation(s) in RCA: 117] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN A retrospective study of 26 patients with degenerative flat back treated with corrective osteotomy. OBJECTIVE To analyze dynamic sagittal imbalance and to elucidate the cause of postoperative persistent stooping in degenerative flat back. SUMMARY OF BACKGROUND DATA Sagittal spinal imbalance in degenerative flat back was more evident on walking, suggesting its dynamic nature. The most puzzling complication in its surgical treatment was postoperative persistent stooping. METHODS This study analyzed 26 surgically treated patients with preoperative gait analysis. Patients were divided into two groups according to postoperative improvement in stooping: Group 1 with marked improvement in stooping and Group 2 with persistent stooping. Various radiographic and gait parameters were compared between the two groups. RESULTS Comparison of radiographic parameters, representing the static status of the spine, did not indicate any clue to the mechanism for persistent stooping. However, comparison of gait parameters, representing the dynamic status of the spine, revealed meaningful differences between the two groups. Among various gait parameters compared, pelvic tilt seemed to be the most important clue. Patients in Group 1 showed posterior pelvic tilt, whereas those in Group 2 showed marked anterior pelvic tilt. CONCLUSION Degenerative flat back could be classified into two types based on pelvic position during walking: one with posterior pelvic tilt and the other with marked anterior pelvic tilt. In the former type, corrective surgery improved the stooping. In the latter, corrective surgery was ineffective, resulting in postoperative persistent stooping.
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Cui G, Yoo JH, Lee JS, Yoo J, Uhm JH, Cha GS, Nam H. Effect of pre-treatment on the surface and electrochemical properties of screen-printed carbon paste electrodes. Analyst 2001; 126:1399-403. [PMID: 11534613 DOI: 10.1039/b102934g] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The effect of various electrochemical pre-treatment methods on the surface and electrochemical properties of screen-printed carbon paste electrodes (SPCE) prepared with three different commercial products was examined. It was observed that a positively charged redox couple, e.g., hexaammineruthenium(III), exhibited quasi-reversible behavior at the untreated SPCE. However, the cyclic voltammograms (CVs) of the SPCE prepared with general-purpose carbon inks did not exhibit clear redox peaks to other representative redox couples [e.g., hexacyanoferrate(III), hexachloroiridate(IV), dopamine, and hydroquinone] without activation. Electrochemical pre-treatment methods were sought in four different aqueous solutions, i.e., sulfuric acid, potassium chloride, sodium hydrogencarbonate, and sodium carbonate, applying various activation potentials. It was found that the pre-treatment procedure in saturated Na2CO3 solution at 1.2 V provides a mild and effective condition for activating the SPCE. By measuring the water contact angles at the SPCE surfaces and recording their SEM images, it was confirmed that the electrochemical pre-treatment effectively removes the organic binders from the surface carbon particles. A prolonged period of activation (> 5 min) or the use of high potentials (> 1.2 V) increased the capacitance of the electrode over 20 microF cm(-2). The pre-treated SPCE behaved like a random array microelectrode, exhibiting a sigmoidal-shaped CV at a slow scan rate. The short pre-anodization method in Na2CO3 solution was generally applicable to most SPCE prepared with general-purpose carbon inks.
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Choi BH, Yi CK, Yoo JH. MRI examination of the TMJ after surgical treatment of condylar fractures. Int J Oral Maxillofac Surg 2001; 30:296-9. [PMID: 11518351 DOI: 10.1054/ijom.2001.0054] [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: 11/18/2022]
Abstract
The position of discs in 20 adult patients whose unilateral condylar fractures were treated by open reduction was investigated by means of magnetic resonance imaging. In four (20%) of the 20 cases, the disc was anteriorly displaced in both the closed mouth and open mouth positions. Three of the four cases had a high condylar neck fracture with dislocation and one had a high condylar neck fracture with displacement. The results of this study showed that repositioning the dislocated condyle did not always lead to anatomical restoration of the joint structures.
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