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J Y Choi

Publications and source records attributed to J Y Choi.

At least 19 recordsLinked to original sources
PubMed2006

SULT1E1 genetic polymorphisms modified the association between phytoestrogen consumption and bone mineral density in healthy Korean women.

Sulfotransferase 1E1 (SULT1E1) catalyze estrogen into sulfate conjugation and is involved in the metabolism of phytoestrogen. A community-based cross-sectional study was conducted on 397 Korean women, to evaluate the association between genetic polymorphisms of SULT1E1 and bone mineral density (BMD) and the combined effect of the genetic polymorphism and phytoestrogen intake for BMD in Korean women. BMDs of the distal radius and the calcaneus were measured by dual-energy X-ray absorptiometry. Genotypes of SULT1E1 IVS1-447 C>A, IVS4-1653 T>C, and *959 G>A were determined by the 5'-nuclease assay (TaqMan). Phytoestrogen intake was estimated by a food-frequency questionnaire validated against multiple 24-hour recalls. Women with the SULT1E1 *959 GG genotype had a 4.5% lower BMD at the distal radius (P (trend )= 0.05) and a 7.9% lower BMD at the calcaneus compared to those with AA genotype (P (trend) < 0.01), whereas the SULT1E1 IVS1-447 CC genotype and IVS4-1653 TT genotype were not associated with BMD. There was no significant trend of BMD with the numbers of CTG-containing haplotypes, but calcaneal BMDs significantly differed between SULT1E1 CTA-CTA haplotype and CTG-CCA haplotype (P < 0.05). When stratified by SULT1E1 genotype, the correlation between phytoestrogen consumption and BMD at the calcaneus was noteworthy in women with SULT1E1 *959 GG genotype (r = 0.25, P = 0.01) or SULT1E1 IVS 4-1653 TT genotype (r = 0.15, P = 0.02). This trend remained significant only in postmenopausal women (r = 0.36, P = 0.01) after multiple testing was corrected by the false discovery rate method. In conclusion, the genetic polymorphism of SULT1E1 *959 G > A was associated with BMD at the distal radius and calcaneus, and the association between phytoestrogen consumption and calcaneal BMD might be modified by this genetic polymorphism.

Absorptiometry, Photon↗
PubMed2006

Spinal extradural arachnoid cyst.

Spinal extradural arachnoid cysts are rare expanding lesions in the spinal canal. They usually present with progressive signs and symptoms caused by spinal cord compression if they enlarge. A comprehensive review about spinal extradural arachnoid cyst is made including the author's own case of a 59-year-old woman with a 6-month history of progressive back pain radiating to both legs. Key points concerning the possible pathogenesis including symptomatology, diagnosis, and the implications for treatment are highlighted. Surgical treatment is curative and this rare clinical entity should be considered in the differential diagnosis of spinal extradural lesions.

Arachnoid Cysts↗
PubMed2006

Surgical treatment for congenital arteriovenous malformation: 10 years' experience.

OBJECTIVES: We report our 10 years experience of the surgical treatment of congenital arteriovenous malformation (AVM). METHODS: We retrospectively reviewed the medical records of 145 patients with AVM who visited Samsung Medical Center in Korea from 1994 to 2003. Among the 145 patients, 21 patients were operated on. Preoperative embolo/sclerotherapy was done in 20 out of the 21 patients. RESULTS: The surgically treated AVMs were 13 cases of head and neck lesions, four cases of upper extremity lesions, one case each of back lesion, uterus lesion, lower extremity lesion and multiple site lesions. There were 10 patients with the extratruncular infiltrating type, nine patients with the extratruncular limited type, one patient with a truncular superficial AV fistula and one patient with a mixed type. Fourteen cases were operated on for cosmetic reasons and since they had localized lesions, and five cases were operated on for tissue necrosis. Fourteen cases were cured by a single operation, yet seven cases needed several sessions of operation to cure the AVM or to promote wound healing after surgery. CONCLUSION: The surgical treatment of AVM is a challenging issue for vascular surgeons. To minimise the complications related to surgery, a multidisciplinary team approach should be considered.

Adolescent↗
PubMed2006

Evaluation of pre- and posttransplantation serum interferon-gamma and soluble CD30 for predicting liver allograft rejection.

The aim of the present study was to identify whether the serum interferon-gamma (IFNgamma), a Th1 cytokine, or soluble CD30 (sCD30), a marker for activation of Th2 cytokine-producing T cells, predict acute cellular rejection episodes among liver graft patients. Pretransplant and posttransplant sera from 32 living donor liver transplant recipients obtained on days 1, 3, and 7 after surgery were tested for serum IFNgamma and sCD30 concentrations using commercial enzyme-linked immunosorbent assay kits. Recipients with an acute rejection episode (ARE) (n=14) displayed significantly higher IFNgamma concentrations pretransplant than did the patients with no ARE (n=18) (P<.05). The pretransplant serum levels of sCD30 were not different between the non-ARE and ARE groups. However, in comparison with the non-ARE group, who showed steadily decreasing serum sCD30 levels after transplantation, 12 among the 14 patients in the ARE group showed increasing sCD30 levels from day 1 to day 3 after transplantation (P<.05). These results suggest that the sCD30 increment during the early period after liver transplantation affects the immune response of rejection. This observation emphasizes the clinical relevance of serum sCD30, in addition to serum IFNgamma, as predictive markers for acute liver graft rejection.

Antigens, CD↗
PubMed2006

Neurothekeoma of the tongue: CT, MR, and FDG PET imaging findings.

We report CT, MR, and fluorodeoxyglucose-positron-emission tomography (FDG-PET) imaging findings of a case of cellular neurothekeoma of the tongue, a rare benign soft-tissue tumor with neural differentiation, occurring in a 15-year-old girl. CT and MR imaging showed a well-defined, well-enhancing submucosal soft-tissue mass in the midline dorsal tongue. There was high FDG uptake on PET scans. Although imaging findings are rather nonspecific, neurothekeoma may be one of diagnostic inclusions of soft-tissue masses of the tongue in a young female patient.

Adolescent↗
PubMed2005

Genetic polymorphisms of OPG, RANK, and ESR1 and bone mineral density in Korean postmenopausal women.

To evaluate the effects of genetic polymorphisms of OPG, RANK, and ESR1, which regulate osteoclastogenesis, on bone mineral density (BMD), a cross-sectional study was conducted in 650 Korean postmenopausal women. BMDs of the distal radius and the calcaneus were measured by dual energy X-ray absorptiometry (DXA). Genetic polymorphisms of OPG 163 A > G, 1181 G > C; RANK 421 C > T, 575 T > C; and ESR1 1335 C > T, 2142 G > A were determined by matrix-assisted laser desorption/ionization-time of flight (MALDI-ToF) mass spectrometry. The differences between the BMDs of the genotypes of OPG, RANK, and ESR1 were analyzed by multiple linear regression model adjusted for age and body mass index. Women with the OPG 1181 CC genotype had higher BMDs at the distal radius (7%) and calcaneus (10%) than those with the GG genotype; and these differences were statistically significant (P = 0.001 and P = 0.007, respectively). A significant association was also observed between RANK 575 T > C and calcaneus BMD (P for trend = 0.017). No significant association was observed between BMDs and the polymorphisms of ESR1. The association between OPG 1181 G > C and BMD was profound in subjects with the RANK 575 TT or ESR1 2142 GG genotypes; women with OPG 1181 CC had higher BMDs at the distal radius (11%) and calcaneus (11%) than those with OPG 1181 GG only in women with RANK 575 TT genotype (P = 0.002 and P = 0.021, respectively). These results suggest that OPG genetic polymorphisms, especially with the RANK 575 TT or ESR1 2142 GG genotypes, are related to low BMD in postmenopausal Korean women.

Adult↗
PubMed2005

Mortality risk factors of Acinetobacter baumannii bacteraemia.

BACKGROUND: Acinetobacter baumannii is one of the most important nosocomial pathogens, and its multiple antibiotic resistance has emerged as an obstacle in the treatment of these infections worldwide. AIMS: To identify risk factors of mortality for A. baumannii bacteraemia. METHODS: A retrospective cohort study of 72 patients with significant A. baumannii bacteraemia was conducted to evaluate risk factors for mortality. RESULTS: The median age of the 72 enrolled patients was 48 years, 96% of the cases were hospital-acquired, and the bacteraemia-related mortality rate was 29% (21 of 72 patients). Univariate analysis revealed that the risk factors for mortality included: an elevated acute physiology and chronic health evaluation (APACHE II) score, receipt of in vitro ineffective definitive antimicrobial therapy, in vitro A. baumannii resistance to cefoperazone/ sulbactam, neutropenia, and presentation with septic shock. Multivariate analysis reveals that the independent risk factors for mortality are neutropenia and elevated APACHE II scores. CONCLUSION: Risk factors such as neutropenia and elevated APACHE II scores are found to be associated with higher mortality rates of A. baumannii bacteraemia. Further study is necessary for the determination of optimal strategies for both the prevention and treatment of these infections.

Acinetobacter Infections↗
PubMed2005

Effects of green tea extract administration on the pharmacokinetics of clozapine in rats.

The pharmacokinetic interaction between clozapine, an atypical antipsychotic with metabolic complications, including weight gain, and green tea consumption has not been evaluated, although green tea is responsible for beneficial effects, including weight reduction, and is widely consumed in the world. Commercial green tea extract (175 mg kg(-1)) or saline was administered orally for 4 days before the oral administration of clozapine (20 mg kg(-1) ) to rats. Plasma concentrations of clozapine were measured up to 5 h after clozapine administration, and then hepatic CYP1A2 expression and activity were determined. There was no significant difference in the elimination half-life of clozapine between the green tea extract and saline groups. However, the time to reach peak concentration (T(max)) was significantly increased by green tea extract. The mean total area under the plasma concentration-time curve (AUC(0-infinity)) and maximal peak plasma concentration (C(max)) of clozapine in the green tea extract group were significantly lower than those of controls. Green tea extract induced a approximately 2-fold increase in hepatic CYP1A2 levels, while the activity increased slightly (by 10% of control). Because of this reduction in AUC and T(max) of clozapine by green tea extract pretreatment, we suggest that both the rate and amount of absorption of clozapine may be reduced by green tea extract, although the hepatic elimination phase may not be significantly altered. Therefore, the clinical implications of the effects of green tea on the bioavailability of clozapine in patients should be further evaluated.

Animals↗
PubMed2005

Advanced management of arteriovenous shunting malformation with transarterial lung perfusion scintigraphy for follow-up assessment.

AIM: The clinical assessment of arteriovenous malformations (AVMs), including treatment response (surgical and/or embolosclerotherapy), has traditionally been done by arteriography, mainly by looking for residual lesions. However, arteriography is disadvantaged as it is an expensive invasive test with high morbidity and provides only limited anatomical information at the qualitative level. Here, transarterial lung perfusion scintigraphy (TLPS), which was developed as a less invasive test for the physiologic assessment of the arteriovenous shunting status of AVM lesions located in the lower extremities, was evaluated for its ability to replace traditional arteriography as a means of following-up treatment results. METHODS: The shunting volume of radioisotope-tagged macro-aggregated albumin injected into the arterial system of the affected limb was counted by TLPS before and after AVM treatment, as a quantitative measure of treatment response. The findings obtained were compared with a matching duplex scan, whole body blood pool scintigraphy (WBBPS) findings, and arteriographic findings. RESULTS: Twenty-one TLPS tests were performed as follow-up assessments on 15 patients with AVM in the extremity, who underwent multistaged embolo/sclerotherapy alone or combined with surgical therapy. These 21 TLPS findings, including 6 interim TLPS results (average 16 months follow-up), provided quantitative measurements of lesion reductions as percentile ratios versus the baseline pretreatment values. Matching posttreatment duplex scan (14 out of 17 sets) and WBBPS (12 out of 15 sets) findings confirmed the posttreatment TLPS assessment. RESULTS: In addition, all 12 available arteriographic studies confirmed the matching TLPS findings. CONCLUSIONS: TLPS can provide accurate information on shunting volume reduction, occurring in response to various treatments during or after the completion of therapy. TLPS, therefore, may be able to replace arteriography, and provide a reliable means of follow-up assessment for the determination of the future treatment strategy.

Adolescent↗
PubMed2004

Primary malignant fibrous histiocytoma extending into spinal canal through intervertebral foramina.

A 60-year-old man was referred to us because of gradual-onset radiculopathy in his left leg for 2 months. Magnetic Resonance Imaging (MRI) of the lumbar spine demonstrated a relatively homogeneous huge mass in the left paravertebral area from L1 to L3 (Fig. 1A, B). Axial MRI scan (Fig. 1C) confirmed the extension of the tumour into the adjacent spinal canal through the neural foramina, forming an extradural mass, which resulted in the compression of both the dural sac and the nerve roots. The patient was operated on by a staged-resection. First, a left retroperitoneal approach was performed for the paraspinal mass. The tumour appeared brown to tan in color and was moderately firm. Nine days after his first operation, the patient underwent a resection of the intraspinal/extradural tumour by a posterior approach. After the left L1-2 hemilaminectomy was performed, the extradural tumour was easily identified, dissected, and completely removed. Microscopically, it was a highly cellular tumour composed of anaplastic cells assuming a gigantic size with bizarre nuclei, which were admixed with inflammatory cells (Fig. 1D). The tumour cells were immunohistochemically characterized by positive staining for vimentin confirming its mesenchymal origin, and CD68 consistent with histiocyte-like qualities (Fig. 1E, F). A diagnosis of inflammatory malignant fibrous histiocytoma (MFH) could be made. Postoperatively, the patient made an uneventful recovery and received radiotherapy as an adjuvant therapy.

Histiocytoma, Benign Fibrous↗
PubMed2004

Acquired syngnathia.

We report two cases of acquired syngnathia, in case 1 probably as a result of a fibrotic tubed pedicle and in case 2 from myositis ossificans. The treatment plan for syngnathia must include not only operation but also a rehabilitation programme (particularly muscle training)

Child, Preschool↗
PubMed2004

Concomitant reconstruction of mandibular basal and alveolar bone with a free fibular flap.

Repair of long-span mandibular defects with a free fibular flap is now a routine procedure. However, the bone height of the neo-mandible after reconstruction with a fibular flap is about half that of the dentulous mandible. When a fibular graft is placed only at the inferior border of the mandible, the resulting vertical discrepancy between the graft segment and the occlusal plane can adversely affect implant mechanics or denture stability and retention. To overcome these problems, we developed a technique for two-strut type mandibular reconstruction. A vascularized fibular segment is used to reconstruct the inferior basal portion of the neo-mandible, while a non-vascularized residual fibular segment is used to simulate the superior alveolar portion. We used this technique in 22 patients. Graft survival, graft resorption, and the ability to place implants were assessed as compared with those after the conventional one-strut type technique. The fibular segment grafted to the alveolar region was removed in one patient with intraoral wound dehiscence and in two with postoperative infection. All vascularized fibular flaps were successful. The resorption rate was 13.6+/-7.2% for non-vascularized segments and 3.0+/-3.7% for vascularized segments. Dental implants were placed in five of our 22 patients. The crown:fixture length ratio was improved to 1:1.7, as compared with a ratio of 1:1.21 with use of a conventional fibular flap. We conclude that our technique is very easy and safe and provides substantially improved lower-lip and cheek support and implant-prosthetic mechanics than conventional procedures for the repair of long-span mandibular defects.

Adult↗
PubMed2004

Synergic in-vitro activity of imipenem and sulbactam against Acinetobacter baumannii.

The interaction between sulbactam and imipenem was evaluated with four clinical isolates of Acinetobacter baumannii, including two isolates resistant to imipenem, one of which produced IMP-1 metallo-beta-lactamase. Two isolates (one of which was imipenem-resistant) were sulbactam-resistant by undefined mechanisms. MICs were determined by standard broth microdilution methods. Time-kill assays with imipenem and sulbactam, alone or in combination at 0.5 x MIC and 1 x MIC, showed a synergic effect in all four isolates of A. baumannii after incubation for 0, 4, 8 and > 24 h at 35 degrees C.

Acinetobacter baumannii↗
PubMed2004

Expression and characterization of a recombinant Cry1Ac crystal protein with enhanced green fluorescent protein in acrystalliferous Bacillus thuringiensis.

AIMS: To investigate fusion expression between Bacillus thuringiensis crystal protein and a foreign protein, the expression of a fusion protein comprised of Cry1Ac, and enhanced green fluorescent protein (EGFP) in B. thuringiensis Cry(-)B strain was examined. METHODS AND RESULTS: The N-terminal fusion expression of EGFP in Cry1Ac was attempted under the control of the native cry1Ac promoter. The EGFP gene was cloned into pProMu and named pProMu-EGFP. The transformant, ProMu-EGFP/CB produced parasporal inclusions that were of bipyramidal-shaped crystals in size ranging from 200 to 300 nm. The fusion protein was approximately 150 kDa and identified by the immunoblot analysis using a Cry1Ac antibody and also a GFP antibody. The LC(50) of the ProMu-EGFP/CB was twofold higher when compared with that by the ProAc/CB. However, the crystal protein produced by the ProMu-EGFP/CB was effective on Plutella xylostella larvae. CONCLUSIONS: The ProMu-EGFP/CB produced bipyramidal shaped and insecticidal crystals comprising fusion proteins. SIGNIFICANCE AND IMPACT OF THE STUDY: Through the N-terminal fusion expression of EGFP and Cry1Ac, expression and crystallization between the B. thuringiensis crystal protein and a foreign protein were validated.

Animals↗
PubMed2004

Contemporary diagnosis and management of venous and arterio-venous shunting malformation by whole body blood pool scintigraphy.

AIM: Various non- to less-invasive tests have been recently introduced in the management of congenital vascular malformations (CVM) and have become essential for the initial diagnostic work-up, largely replacing the traditional role of invasive tests. Whole body blood pool scintigraphy (WBBPS) was initially adopted as a supplementary test to reinforce other well-established essential diagnostic tests, and has been used extensively together in our Clinic, for years. We have evaluated WBBPS retrospectively for the diagnosis of venous malformation (VM) and arterio-venous malformation (AVM), and also for a further possible role for the interim assessment of treatment results during multistaged embolo/sclerotherapy. METHODS: Of 123 VMs and 48 AVMs selected for various treatments, 80 patients (66 VMs and 14 AVMs) were reviewed. The reliability of WBBPS as an initial diagnostic tool for VMs and AVM was assessed first by comparing its findings with matching MRI and/or duplex scan findings. These 80 patients underwent embolo/sclerotherapy with absolute ethanol mostly for VM, and N-butyl cyanoacrylate for AVM. A total of 251 sessions were performed either as a primary treatment independently or in conjunction with surgical treatment preoperatively. Thirty-six patients were available in terms of the subsequent review of the treatment results, to compare their 72 post-therapy WBBPS findings with matching duplex scan and MRI findings. The WBBPS assessment of treatment response was based on the percentage reduction of abnormal blood pooling over the region of interest (ROI) from baseline (initial) value. Treatment response was also qualitatively and semi-quantitatively assessed according to the degree of abnormal blood pool reduction. RESULTS: Of the 80 CVM (66 VM and 14 AVM) patients, 61 of 66 WBBPS findings of VM on initial diagnosis were confirmed as true-positive. Twelve of 14 AVMs were also confirmed as WBBPS true-positive findings. The sensitivity of WBBPS for the initial diagnosis was 93.8% (61/65) for VM and 92.3% (12/13) for AVM. The positive predictive value was 98.4% (61/62) for VM and 92.3% (12/13) for AVM. Of 72 post-therapy WBBPS performed for follow-up assessment of the results of treatment on 36 patients, 52 WBBPS showed positive findings qualitatively and/or quantitatively, the remaining 20 were negative. Fifty-one of the 52 WBBPS-positive findings were true-positive and 18 of the 20 were true-negative. Hence, WBBPS for follow-up assessment showed a sensitivity of 96% (51/53); a specificity of 95% (18/19); a positive predictive value of 98% (51/52); and a negative predictive value of 90% (18/20). CONCLUSIONS: Contemporary management of CVMs can be improved by using WBBPS, which is a less expensive, simple, and safe non-invasive test, especially for venous and arterio-venous malformations. WBBPS is a cost-effective and practical test with dependable accuracy for the assessment of treatment results, especially for interim measurements during multistage embolo/sclerotherapy.

Adolescent↗
PubMed2003

Coexistence of ductal constriction and closure of the foramen ovale in utero.

We report a fetus with an unusual combination of a narrow ductus arteriosus (DA) and foramen ovale. A pregnant mother was referred at 26 weeks of gestation for fetal pericardial effusion. Fetal echocardiography showed pericardial effusion, right atrial enlargement, right ventricular hypertrophy, and tricuspid regurgitation. The DA looked tortuous with S-shaped kinking. The atrial septum primum bulged into the left atrium. Color Doppler did not show any flow across the atrial septum. Cesarean section was performed at 31 weeks of gestation. Admission to intensive care was required after delivery, but the infant gradually improved and was discharged home without any sequela.

Adult↗
PubMed2003

Production of ultrahigh purity copper using waste copper nitrate solution.

The production of ultrahigh purity copper (99.9999%) by electrolysis in the presence of a cementation barrier has been attempted employing a waste nitric copper etching solution as the electrolyte. The amount of copper deposited on the cathode increased almost linearly with electrolysis time and the purity of copper was observed to increase as the electrolyte concentration was increased. At some point, however, as the electrolyte concentration increased, the purity of copper decreased slightly. As the total surface area of cementation barrier increased, the purity of product increased. The electrolyte temperature should be maintained below 35 degrees C in the range of investigated electrolysis conditions to obtain the ultrahigh purity copper. Considering that several industrial waste solutions contain valuable metallic components the result of present study may support a claim that electrowinning is a very desirable process for their treatment and recovery.

Conservation of Natural Resources↗