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Eun-Ju Lee

Publications and source records attributed to Eun-Ju Lee.

13 recordsLinked to original sources
PubMed2006

ACE inhibition can improve orthostatic proteinuria associated with nutcracker syndrome.

Left renal vein entrapment syndrome (nutcracker syndrome) was documented by magnetic resonance angiography (MRA) as a cause of orthostatic proteinuria in a 14-year-old girl female adolescent. Because of continuous proteinuria we performed a left renal biopsy which showed moderate mesangial hypercellularity. Her overt orthostatic proteinuria disappeared after a treatment of angiotensin-converting enzyme (ACE) inhibition. Nutcracker syndrome remains a rare but important cause of elevated protein excretion, which can induce mesangial changes and be improved by ACE inhibitor treatment.

Adolescent↗
PubMed2006

Alternative splicing variants of IRF-1 lacking exons 7, 8, and 9 in cervical cancer.

The two previously identified major splice variants of interferon regulatory factor 1 (IRF-1) do not appear to affect IRF-1-mediated gene activation. We searched for additional splice variants and examined their effect on wild-type IRF-1. RT-PCR experiments using normal and malignant human cervical tissue samples revealed five variants lacking some combination of exons 7, 8, and 9; their expression levels were higher in the malignant samples. These variants had predicted deletions of the functional domain or truncated protein isoforms, had different transcriptional activities, and attenuated transcriptional activity of IRF-1. Unlike the cell cycle-dependent IRF-1 transcript, the splice variant mRNA levels remained consistent throughout the cell cycle. The variant proteins were more stable than the IRF-1 protein, which may explain the strong inhibition of IRF-1 transcription in the presence of relatively small quantities of the alternative transcripts. In conclusion, alternative splicing in exons 7, 8, and 9 is an important mechanism for negatively regulating IRF-1 in cervical cancer.

Alternative Splicing↗
PubMed2005

The alpha-effect in reactions of sp-hybridized carbon atom: Michael-type reactions of 1-aryl-2-propyn-1-ones with primary amines.

[reaction: see text] Second-order rate constants (kN) have been measured for the Michael-type reaction of 1-(X-substituted phenyl)-2-propyn-1-ones (2a-f) with a series of primary amines in H2O at 25.0 +/- 0.1 degree C. A linear Brønsted-type plot with a small beta(nuc) value (beta(nuc) = 0.30) has been obtained for the reactions of 1-phenyl-2-propyn-1-one (2c) with non-alpha-nucleophile amines. Hydrazine is more reactive than other primary amines of similar basicity (e.g., glycylglycine and glycine ethyl ester) and results in a positive deviation from the linear Brønsted-type plot. The reactions of 2a-f with hydrazine exhibit a linear Hammett plot, while those with non-alpha-nucleophile amines give linear Yukawa-Tsuno plots, indicating that the electronic nature of the substituent X does not affect the reaction mechanism. The alpha-effect increases as the substituent X in the phenyl ring of 2a-f becomes a stronger electron-donating group. However, the magnitude of the alpha-effect for the reactions of 2a-f is small (e.g., kN(hydrazine)/kN(glycylglycine) = 4.6-13) regardless of the electronic nature of the substituent X. The small beta(nuc) has been suggested to be responsible for the small alpha-effect. A solvent kinetic isotope effect (e.g., kN(H2O)/kN(D2O) = 1.86) was observed for the reaction with hydrazine but absent for the reactions with non-alpha-nucleophile amines. The reactions with hydrazine and other primary amines have been suggested to proceed through a five-membered intramolecular H-bonding structure VI and a six-membered intermolecular H-bonding structure VII, respectively. The transition state modeled on VI can account for the substituent dependent alpha-effect and the difference in the solvent kinetic isotope effect exhibited by the reactions with hydrazine and other primary amines. It has been proposed that the beta(nuc) value is more important than the hybridization type of the reaction site to determine the magnitude of the alpha-effect.

Journal Article↗
PubMed2005

Proteome analysis of rat pancreas induced by pancreatectomy.

The previous study demonstrated that the streptozotocin (STZ)-induced diabetic mice can be cured by injecting the regenerating pancreatic extract (RPE) of the partially pancreatectomized Wistar-Kyoto rats. In this study, to characterize the complex pattern of protein expression in RPE, the proteins of altered expression level after the pancreatectomy were identified by 2-dimensional electrophoresis (2-DE) and mass spectrometry. Of 76 significantly up- or down-regulated protein spots, 61 were identified by MALDI-TOF/MS. Moreover, the whole RPE was fractionated into 4 groups using an anion-exchange chromatography and each fraction's cell proliferating activity was measured by MTT assay. Compared to the normal pancreatic extract, fraction 3 and 4 of RPE showed the maximal cell proliferating activity. On 2-DE of 3 and 4 fractions, a total of 10 spots, which are differentially expressed after the pancreatectomy, were identified by MS/MS. Of these identified proteins, Reg III which might be functionally associated with well known regenerating factor (Reg I) was found. Taken together, our results demonstrated that the differential protein expression associated with pancreas regeneration could be sought by 2-DE and mass spectroscopy and suggested that the pre-fractionation method combined with in vitro cell proliferation assay is effectively used to pinpoint the active components for pancreas regeneration.

Animals↗
PubMed2005

Insulin-like growth factor binding protein 2 promotes ovarian cancer cell invasion.

BACKGROUND: Insulin-like growth factor binding protein 2 (IGFBP2) is overexpressed in ovarian malignant tissues and in the serum and cystic fluid of ovarian cancer patients, suggesting an important role of IGFBP2 in the biology of ovarian cancer. The purpose of this study was to assess the role of increased IGFBP2 in ovarian cancer cells. RESULTS: Using western blotting and tissue microarray analyses, we showed that IGFBP2 was frequently overexpressed in ovarian carcinomas compared with normal ovarian tissues. Furthermore, IGFBP2 was significantly overexpressed in invasive serous ovarian carcinomas compared with borderline serous ovarian tumors. To test whether increased IGFBP2 contributes to the highly invasive nature of ovarian cancer cells, we generated IGFBP2-overexpressing cells from an SKOV3 ovarian cancer cell line, which has a very low level of endogenous IGFBP2. A Matrigel invasion assay showed that these IGFBP2-overexpressing cells were more invasive than the control cells. We then designed small interference RNA (siRNA) molecules that attenuated IGFBP2 expression in PA-1 ovarian cancer cells, which have a high level of endogenous IGFBP2. The Matrigel invasion assay showed that the attenuation of IGFBP2 expression indeed decreased the invasiveness of PA-1 cells. CONCLUSIONS: We therefore showed that IGFBP2 enhances the invasion capacity of ovarian cancer cells. Blockage of IGFBP2 may thus constitute a viable strategy for targeted cancer therapy.

Cell Line, Tumor↗
PubMed2005

Transarterial embolization for postoperative hemorrhage after abdominal surgery.

The study goal was to evaluate the efficacy, safety, and clinical outcome of transarterial embolization for postoperative hemorrhage after abdominal surgery. Thirty-three patients were referred for angiography because of gastrointestinal or intra-abdominal bleeding after abdominal surgery. Urgent angiography and transarterial embolization was performed in all 33 patients. The clinical and angiographic features were retrospectively reviewed. Angiography revealed a discrete bleeding focus in 26 (79%) of 33 patients. Transarterial embolization was technically successful in 24 (92%) of 26 patients with a discrete bleeding focus. Rebleeding occurred in four (17%) of 24 patients. They were successfully managed with repeat embolization. There was no procedure-related complication during follow-up period. Angiography has a high detection rate of bleeding site in patients with postoperative hemorrhage after abdominal surgery. Transarterial embolization is considered to be an effective and safe means in the management of postoperative hemorrhage.

Abdominal Injuries↗
PubMed2004

Human keratin 14 driven HPV 16 E6/E7 transgenic mice exhibit hyperkeratinosis.

Human papillomavirus type 16 (HPV16) has been known as a major causative factor for the development of uterine cervical carcinomas. To investigate the in vivo activity of HPV16 expressed in squamous epithelia, transgenic mice harboring HPV16 E6/E7 with human keratin 14 (hK14) promoter were generated. Grossly, hK14 driven HPV16 E6/E7 transgenic mice exhibited multiple phenotypes, including wrinkled skin that was apparent prior to the appearance of hair in neonates, thickened ears, and loss of hair in adults. Transgenic mice with phenotype exhibiting severe wrinkled skin and a lack of hair growth died at the age of 3-4 weeks. Histological analysis revealed that in transgenic mice survived beyond the initial 3-4 weeks, HPV16 E6/E7 causes epidermal hyperplasia in multiple transgenic lineages with high incidence of transgene penetration. This epithelial hyperplasia was characterized by an expansion of the proliferating compartment and keratinocytes, and was associated with hyperkeratosis. Such activities were significantly higher in the skin of transgenic mice than that of the normal mice. Thus, these transgenic mice appeared to be useful for the expression of HPV16 E6/E7 gene and subsequent analysis on hyperkeratosis.

Animals↗
PubMed2004

Analysis of differentially regulated proteins in TM4 cells treated with bisphenol A.

BPA, bisphenol A, a monomer of epoxy resins and polycarbonate plastic, is used in many consumer products including the plastic linings of cans for food and babies' bottles. BPA has been reported to cause reproductive toxicity and affects cells in rats and mice at high doses. In this study, the effect of BPA on protein expression in TM4 cells (a mouse Sertoli cell line) known to play an essential role in Spermatogenesis was investigated by two-dimensional electrophoresis (2-DE). After 16 h exposure to 50, 100, 150, 200, and 250 microM of BPA, the viability of TM4 cells decreased to about 90, 85, 78, 55, and 30% of control respectively. Approximately 800 protein spots in TM4 cells were analyzed by 2-DE with pH 4-7 linear immobilized pH gradient (IPG) Dry Strip, and 11 proteins which showed significantly different expression levels were identified by matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS). Among these, HSP 27 and placental calcium binding protein may be proteins differentially expressed by BPA exposure.

Animals↗
PubMed2003

One-pot hydrogenation conditions for a sequential process to (+)-monomorine.

(+)-Monomorine has been synthesized under mild hydrogenation conditions initiating deprotection followed by intramolecular, sequential reductive amination reactions. The precursors could be prepared concisely using B-alkyl Suzuki cross coupling of a chiral homoallylamine and a vinyl iodide or an iodofuran derivative.

Alkaloids↗
PubMed2003

Comparative analysis of collagen membranes for the treatment of implant dehiscence defects.

Guided bone regeneration (GBR) evolved from the concept of guided tissue regeneration (GTR) and has been used for reconstructing sites with bone deficiencies associated with dental implants. For GBR, the use of absorbable collagen membranes has been increasing, but, at present, scientific information on the use of collagen membranes for GBR is limited. This study was aimed to clinically and histomorphometrically compare two collagen membranes, Bio-Gide(R) and BioMend ExtendTM, for the treatment of implant dehiscence defects in eight mongrel dogs. Implant dehiscence defects were surgically created in edentulous ridges, followed by the placement of three endosseous implants bilaterally in the mandible. Each implant dehiscence defect was randomly assigned to one of three treatment groups: (1) control (no membrane), (2) porcine dermis collagen barrier (Bio-Gide) or (3) bovine tendon collagen barrier (BioMend Extend). Dogs were sacrificed at 4 and 16 weeks (four dogs each) after treatment. Histomorphometric analysis included percentage linear bone fill (LF), new bone-to-implant contact (BIC) and area of new bone fill (BF). The results of the study revealed no significant differences among groups for any parameter at 4 weeks. However, at 16 weeks, more LF, BIC, and BF were noted in the membrane-treated groups than controls. BioMend Extend-treated defects demonstrated significantly greater BIC than control (P < 0.05) at this time point. BIC at 16 weeks was significantly greater than 4-week BIC (P < 0.05). Membrane exposure occurred in 9 out of 15 sites examined, resulting in significantly less LF and BIC than the sites without membrane exposure (P < 0.05). The results of this study indicate that: (1) GBR treatment with collagen membranes may significantly enhance bone regeneration, manifested at late stage (16 weeks) of healing; and (2) space maintenance and membrane coverage were the two most important factors affecting GBR using bioabsorbable collagen membranes.

Absorbable Implants↗
PubMed2002

Intrathecal carbachol and clonidine produce a synergistic antiallodynic effect in rats with a nerve ligation injury.

PURPOSE: Antiallodynic effects have been demonstrated after intrathecal administration of alpha-2 adrenoceptor agonists and cholinesterase inhibitors in rats. Intrathecal carbachol also increases the activity of cholinergic receptor system at the spinal level. However, there is no study regarding the antagonism of carbachol on touch-evoked allodynia and the interaction with clonidine. This study examines the intrathecal interaction between two drugs in a rat model of nerve ligation injury. METHODS: Rats were prepared with tight ligation of the left L5-6 spinal nerves and chronic intrathecal catheter implantation. Tactile allodynia was measured by using application of von Frey filaments to the lesioned hindpaw. Carbachol (0.3-10 microg) and clonidine (1-30 microg) were administered to obtain the dose-response curves and the 50% effective dose (ED(50)) for each drug. Fractions of ED(50) values (1/2, 1/4, 1/8, and 1/16) were administered intrathecally to establish the ED(50) of the carbachol-clonidine combination. Isobolographic and fractional analyses of drug interaction were performed. RESULTS: Intrathecal carbachol and clonidine alone produced a dose-dependent reduction of tactile allodynia without severe motor weakness or sedation. A carbachol-clonidine combination produced a dose-dependent increase in withdrawal threshold of the lesioned hindpaw with a reduced incidence and magnitude of side effects. Both analyses revealed a synergistic interaction after the coadministration of carbachol and clonidine. CONCLUSIONS: This study indicates that carbachol, like clonidine, provides a moderate antagonism on touch-evoked allodynia at the spinal level. The results suggest that intrathecally administered carbachol is synergistic when combined with clonidine.

Animals↗
PubMed2002

Comparative histologic analysis of coronally advanced flap with and without collagen membrane for root coverage.

BACKGROUND: Guided tissue regeneration (GTR)-based root coverage has been utilized to correct gingival recession defects with promising results. However, limited histologic information is available. Therefore, the aims of this study were to clinically and histologically evaluate the efficacy of GTR-based root coverage using collagen membrane (GTRC) and to compare the healing response to that of coronally advanced flaps (CAF). METHODS: Standardized gingival recession defects were surgically created on the labial surfaces of the maxillary cuspids of 8 mongrel dogs. Plaque was allowed to accumulate for 8 weeks to develop a plaque-infected recession defect. Full-mouth scaling and root planing was then performed coincident with 4 weeks of oral hygiene. Defects were randomly assigned to receive either GTRC or CAF surgery. Four dogs each were sacrificed at 4 and 16 weeks post-treatment. Clinical measurements included: percent root coverage, the amount of keratinized gingiva (KG), and probing depth (PD). Sulcular depth, junctional epithelium and connective tissue attachment, new cementum formation, and new bone formation were evaluated histomorphometrically. RESULTS: Clinically, both treatments (CAF and GTRC) achieved statistically significant (P <0.05) root coverage compared to baseline. KG was significantly increased in CAF-treated sites at 16 weeks, while no significant differences were found for other clinical parameters between treatments. Histometrically, GTRC showed a statistically significant increase of new attachment and newly formed connective tissue when compared to CAF at 16 weeks. CONCLUSION: Within the limits of this preclinical study, both GTRC and CAF can be successfully used for the treatment of gingival recession defects.

Absorbable Implants↗