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Biomedical subjects

S G Lee

Publications and source records attributed to S G Lee.

At least 19 recordsLinked to original sources
PubMed1999

Predictors of diffuse-type in-stent restenosis after coronary stent implantation.

Diffuse-type in-stent restenosis (ISR) is associated with higher rate of restenosis after balloon angioplasty, requiring new therapeutic modalities; therefore, it is clinically important to identify the determinants of diffuse-type ISR. We evaluate the clinical and angiographic variables to predict diffuse-type ISR after coronary stent placement. Two hundred and ten ISR lesions in 196 patients (diffuse ISR, 114 lesions; focal ISR, 96 lesions) were reviewed in this study. Clinical, procedural and quantitative coronary angiographic parameters were analyzed. Diffuse-type ISR was defined as a > or = 50% lumen narrowing and > or = 10-mm length. Univariate analysis revealed that initial lesion length, smaller vessel size, diabetes, multivessel disease, multiple stents, and long stent were significantly associated with diffuse-type ISR. However, diabetes was the only independent predictor of diffuse-type ISR by stepwise multiple regression analysis (OR, 3.3; 95% CI, 1.4-7.4, P = 0.001). Diabetes was associated with diffuse-type ISR after coronary stent placement. It may reflect enhanced rate of neointimal hyperplasia within the stent in diabetic patients.

Angioplasty, Balloon, Coronary↗
PubMed1999

Percutaneous hot saline injection therapy: effectiveness in large hepatocellular carcinoma.

PURPOSE: To report on the efficacy of percutaneous hot saline injection therapy (PSIT) in the treatment of large hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Twenty-nine patients with 31 HCCs underwent PSIT. Physiologic saline was mixed with contrast medium and Lipiodol; this mixture was boiled and injected into the tumor. Mean tumor diameter was 7.0 cm. Initial regression rates were evaluated at 3-month interval with computed tomography (CT) and alpha-fetoprotein level measurement. Cumulative survival rates were calculated with the Kaplan-Meier method. Multivariate analysis using Cox's proportional hazard regression model was performed to determine the significant prognostic factors. RESULTS: Initial regression rate for all tumors at a 3-month interval was 42% (13 of 31 tumors) and the median survival was 10.0 months (range, 3.0-36.0 months). The significant prognostic factors were encapsulated tumors, tumors less than 10 cm in diameter, tumors with even saline dispersion, tumors with initial regression at 3-month follow-up, and TNM stage II or III rather than IV. CONCLUSION: PSIT is a feasible alternative treatment for a large HCC when transcatheter arterial chemoembolization is not feasible or has failed.

Adult↗
PubMed1998

Locoregional response and increased natural killer activity after intratumoral injection of HLA-B7/beta2-microglobulin gene in patients with cancer.

The purpose of this study was to assess the therapeutic potential of injecting the gene for HLA-B7/beta2-microglobulin into the subcutaneous metastatic nodules of patients who are refractory to conventional treatments. The nine patients evaluated were divided into three groups and given escalating doses of DNA (20, 40, and 100 microg of the HLA-B7 plasmid DNA/lipid complex for each group) every 2 weeks. Biopsy specimens from the treated tumor nodules of all nine patients were positive for the presence of DNA and for HLA-B7 mRNA expression. Moreover, in six of the nine patients, immunohistology of tumor biopsy samples revealed the expression of recombinant HLA-B7 protein. Also, all nine patients showed an increase in NK activity in their circulating peripheral blood lymphocytes. In two lung cancer patients, one partial and one mixed response was observed after gene transfer. These responses were confined to the treated nodules and the untreated locoregional lymph nodes; the lung masses showed no regression. Remission durations were 14 and 6 weeks, respectively, and in a total of 35 cycles no significant toxicities were observed. Immunohistologic analysis revealed an increased infiltration of CD4+ T cells, macrophages, and NK cells after therapy. In two responding cases, direct intratumoral injection of an allogeneic class I gene could elicit an antitumor response in locoregional areas, possibly through the activation of NK cells.

Adult↗
PubMed1998

Synergistic anti-tumor effects with co-expression of GM-CSF and IFN-gamma in murine tumors.

We explored the potential therapeutic benefit of introducing GM-CSF, IFN-gamma or a combination of both factors into CT26 tumor cells. CT26 cells secreting either GM-CSF or IFN-gamma exhibited delayed tumorigenicity; however, cells expressing both GM-CSF and IFN-gamma did not form tumors. Even when wild type CT26 cells were introduced into a distant site of mice that had been inoculated with CT26/GM-CSF/IFN-gamma cells, no tumors were generated. Furthermore, when we injected GM-CSF + IFN-gamma cells into animals bearing established tumors, the tumors were either rejected or their development was delayed, suggesting that synergistic effects were induced against these tumors via a systemic immune response. Histopathological examination of the tumors injected with cells expressing GM-CSF and IFN-gamma combined showed necrosis and few signs of malignancy. The growth of tumors from mice treated with CT26/GM-CSF/IFN-gamma cells exhibited a delay in tumor formation and no effects were seen in athymic nude mice, which are deficient in T lymphocytes, or in splenectomized nude mice, which are deficient in natural killer (NK) cells, respectively. Our data indicate a dual role for T and NK cells in mediating the anti-tumor activity of this therapy. Our results suggest that transduction of tumor cells with both GM-CSF + IFN-gamma results in a powerful synergistic effect of the 2 cytokines that is of greater therapeutic benefit than transduction with either cytokine alone.

Adenocarcinoma↗
PubMed1998

Immediate and long-term outcomes of rotational atherectomy versus balloon angioplasty alone for treatment of diffuse in-stent restenosis.

This study was performed to compare the effects of rotational atherectomy (RA) plus balloon angioplasty (BA) with those of BA alone for treatment of diffuse in-stent restenosis. RA+BA or BA alone was performed in a consecutive, prospective (not randomized) manner in 81 patients with 81 diffuse in-stent restenotic lesions (lesion length > 10 mm): 36 patients underwent RA+BA, and 45 patients BA. Clinical recurrence was the primary end point of this study, and was defined as angina associated with objective evidence of myocardial ischemia on stress testing. Mean follow-up duration was 277 +/- 109 days. In the BA group, acute lumen gain after repeat intervention was significantly lower than that of the original stenting procedure (1.94 +/- 0.63 vs 2.37 +/- 0.51 mm, p <0.05). In the RA + BA group, however, acute lumen gain of repeat intervention was similar to that of the original stenting procedure (2.16 +/- 0.52 vs 2.26 +/- 0.66 mm). Clinical recurrence rate at 6 months follow-up was significantly lower in the RA+BA group than in the BA group (25% vs 47%, p <0.05). Clinical events (death, myocardial infarction, repeat intervention) occurred in 6.7% (3 of 45) of patients in the BA group, but in no patient in the RA+BA group during the follow-up period. The long-term angina-free survival rate was significantly higher in the RA+BA group than in the BA group (72% vs 49%, p = 0.02). In conclusion, RA+BA seems to be a more effective therapeutic modality than BA alone for treatment of diffuse in-stent restenosis.

Aged↗
PubMed1998

Identification of glycinin in vivo as a polyamine-conjugated protein via a gamma-glutamyl linkage.

To identify a polyamine-conjugated protein by the action of transglutaminase in the absence of radiolabelled polyamine, extracts prepared from the leaves and developing soybean seeds were investigated for the specific activity of transglutaminase and the content of free polyamines. We identified the major storage protein, glycinin, as a polyamine-conjugated protein. This was established by the following procedures: (1) immunolocalization with antibody against putrescine prepared in rabbit against putrescine-BSA conjugate; (2) immunocross-reactivity on nitrocellulose transblot of the purified glycinin subunits by using antibody against putrescine; (3) identification of polyamines in acid hydrolysates of purified glycinin; (4) release of polyamines in proteolytic digests through the catalytic action of gamma-glutamylamine cyclotransferase, an enzyme specific for the disassembly of gamma-glutamylamines. The activity of gamma-glutamylamine cyclotransferase was also identified in soybean seeds.

Antibodies↗
PubMed1998

Isolation of a novel pentachlorophenol-degrading bacterium, Pseudomonas sp. Bu34.

A pentachlorophenol (PCP)-degrading bacterium was isolated from possible PCP-contaminated soil from Pusan, Korea and identified as a member of the genus Pseudomonas. It used PCP as its sole source of carbon and energy. This micro-organism was capable of degrading PCP more effectively, certified by the increase in cell density and the decrease in PCP substrate. Pseudomonas sp. Bu34 was able to degrade a much higher concentration of PCP (4000 mg l-1) than any previously reported PCP-degrading bacteria and fungi and to grow in mineral salts solution containing one of a variety of chlorophenols. In non-acclimated strain Bu34, the cell number decreased from 87 to 99.9% in 75-4000 mg l-1 PCP at 24 h. In the acclimated strain the PCP toxic effect did not appear with 75 mg l-1 PCP treatment, but 1000-4000 mg l-1 PCP decreased the cell number of strain Bu34 by 25% to 24 h and then the cell number slightly increased at 48 h. Therefore, it suggested that the maximum resistance of acclimated strain Bu34 to PCP was 4000 mg l-1 PCP. We suggest that strain Bu34 could be used as a micro-organism for the bioremediation of highly PCP-contaminated soils, water or wood products.

Bacterial Typing Techniques↗
PubMed1998

Abscess-forming neutrophilic dermatosis: report of three cases associated with hemopathies.

BACKGROUND: The development of different types of neutrophilic dermatosis is reported to occur in the course of malignant hemopathies. These concern mainly Sweet's syndrome, pyoderma gangrenosum, erythema elevatum et diutinum and neutrophilic eccrine hidradenitis. OBSERVATIONS: We have recently encountered the cases of 3 patients who presented all with multiple acneiform papules and dome-shaped aseptic abscesses leaving scars. Pus was sterile in all except case 3 in which slight Staphylococcus aureus growth was shown. However, in this patient, only steroids were effective demonstrating that this bacterium was not responsible for the disease. Histopathology disclosed a dense dermal polymorphonuclear neutrophil infiltrate and some mononuclear cells. Two of these patients had myelodysplastic syndromes while one had IgA myeloma. CONCLUSION: Abscess-forming neutrophilic dermatosis seems to be another type of neutrophilic dermatosis associated with hematological malignancies.

Abscess↗
PubMed1998

MR cholangiopancreatography of pancreaticobiliary diseases: comparing single-shot RARE and multislice HASTE sequences.

OBJECTIVE: In this study, we compared the single-shot rapid acquisition with relaxation enhancement (RARE) sequence with the multislice half-Fourier acquisition single-shot turbo spin-echo (HASTE) sequence to assess the ability of each technique to show various pancreaticobiliary diseases using MR cholangiopancreatography. SUBJECTS AND METHODS: MR cholangiopancreatography was performed using both the single-shot RARE and the multislice HASTE pulse sequences in 80 consecutive subjects in whom we had proof of a range of diagnoses. The study population included healthy subjects (n = 9), patients with benign lesions (n = 41), and patients with malignant lesions (n = 30). We analyzed each image using the following criteria: the cause of the lesions, the image quality (i.e., the amount of artifact and the sharpness of anatomic structures such as the right and left hepatic ducts, the extrahepatic bile duct, and the main pancreatic duct), and the reviewers' preference of images. The images were evaluated independently by two radiologists who were unaware of the results of the other cholangiopancreatographic sequence and of the diagnosis. RESULTS: Artifacts were less prominent in images that were obtained using the single-shot RARE sequence (p = .0192); however, the sharpness of anatomic structures was the same using either sequence (p = .1673). For images that were obtained using the single-shot RARE technique, the sensitivity, specificity, and accuracy in distinguishing malignant from other abnormalities were 83%, 78%, and 80%, respectively; for the multislice HASTE technique, these values were 77%, 72%, and 74%, respectively (p > .05). Disease-specific accuracy in determining the correct diagnosis was 54% and 59%, respectively (p > .05). In patients in whom all the ducts needed to be defined, the single-shot RARE technique was preferred to the multislice HASTE technique (p < .01). CONCLUSION: The single-shot RARE technique shows fewer artifacts and is preferred to the multislice HASTE technique. However, both techniques show the same degree of sharpness of anatomic structures, both are able to reveal malignant diseases, and both provide enough information to determine a specific diagnosis.

Adult↗
PubMed1998

Regeneration of graft liver in adult-to-adult living donor liver transplantation using a left lobe graft.

Graft size-matching is one of the critical concerns in adult-to-adult living donor liver transplantation (ATALDLT). In this study, we evaluated regeneration of a small-for-size graft less than 50% of the standard liver volume (SLV). We reviewed nine patients of united network of organ sharing (UNOS) status 2 or 3 who had undergone ATALDLT with a left lobe graft. For the comparison of liver regeneration, 20 hepatectomized patients for biliary malignancy were selected as non-transplant control group. In the ATALDLT group, graft size ranged from 30 to 49% of the SLV of recipients and their regeneration rates were 158%, 182%, 200% and 185% after 1,2, 3 and 4 weeks following transplantation, respectively. In the control group, preoperative volume of left lobe to whole liver volume ranged between 40 and 54% and their regeneration rates were 145%, 156%, 163% and 177% after 1,2, 3 and 4 weeks following extended right lobectomy, respectively. There was no statistical difference in regeneration rates between two groups. In the ATALDLT group, serum aspartate aminotransferase showed the median peak level of 198 IU/L on the first postoperative day and it was normalized within one week. Recovery of bilirubin clearance lagged behind rapid volume regeneration by about one week. Two patients died of sepsis. We postulate that the regenerative power of small-for-size grafts from living donors is preserved, although time-lag between volume regeneration and metabolic capability occurs in small-for-size grafts, when the initial graft volume meets metabolic demands during the early postoperative days.

Adult↗
PubMed1998

Comparison of slotted tube versus coil stent implantation for ostial left anterior descending coronary artery stenosis: initial and late clinical outcomes.

Balloon angioplasty of ostial left anterior descending coronary artery (LAD) lesions has been associated with a high rate of acute complications and late restenosis. Recently, coronary stenting has been proposed as an effective treatment modality for ostial LAD lesions. To evaluate the effects of stent design on the development of late restenosis, we retrospectively analyzed the efficacy of slotted-tube stent implantation (40 patients, Palmaz-Schatz stent) and coil stent implantation (15 patients, tantalum Cordis stent) of ostial LAD stenosis. Six-month angiographic follow-up data were obtained in 31 patients (82%) with slotted-tube stent implantation and 12 patients (86%) with coil stent implantation. Angiographic restenosis was defined as > or =50% diameter stenosis. The angiographic restenosis rate was significantly lower in slotted-tube stent implantation (32%) than in coil stent implantation (67%) (p<0.05). Target lesion revascularization rate of slotted tube stent implantation was significantly lower (26%) than that of coil stent implantation (57%) (p<0.05). Coil stent implantation of ostial left anterior descending artery lesions was associated with higher late restenosis compared with slotted tube stent implantation. In conclusion, slotted-tube stent implantation might be considered to improve late clinical outcomes of ostial LAD lesions.

Angioplasty, Balloon, Coronary↗
PubMed1998

Collaborative workspace for multimedia medical conferencing.

We propose an approach for collaborative workspace management in medical conferencing. A collaborative workspace is a virtual data space shared between medical experts for working out solutions collaboratively while conferencing. Our approach provides medical users with an integrated view of various kinds of multimedia patient data and a unified control over the workspace. For data navigation and conferencing, a tree-like navigation tool, which we named the patient record tree, is provided. And we classify patient data, which is the object of medical collaborative works, into six basic types, and provide a view template for displaying each of these types.

Cooperative Behavior↗
PubMed1998

MR of hippocampal sclerosis: comparison of qualitative and quantitative assessments.

PURPOSE: Our goal was to compare the diagnostic accuracy of subjective visual assessment versus MR volumetry in evaluating hippocampal sclerosis and to determine whether MR volumetry is needed in the lateralization of this disease process. METHODS: MR imaging findings were studied retrospectively in 48 patients who underwent surgery for temporal lobe epilepsy and were compared with findings at MR volumetry on an Allegro workstation. Both visual assessment and volumetry were carried out in a blinded fashion with oblique coronal T1-weighted three-dimensional MP-RAGE images obtained on either 1.0-T or 1.5-T units. Normal right-left volumetric differences were recorded in 30 control subjects. The optimum cutoff threshold value for right-left volumetric differences in the sensitivity and specificity of volumetric measurement was obtained from receiver operating characteristic analysis. RESULTS: Sensitivity, specificity, positive and negative predictive values, and accuracy of visual assessment were 86%, 83%, 86%, 83%, and 85%, respectively. For MR volumetry, with the optimum cutoff threshold value of right-left difference at 0.3 cm3, sensitivity, specificity, positive and negative predictive values, and accuracy were 81%, 82%, 87%, 83%, and 85%, respectively. CONCLUSION: Visual assessment was slightly superior to or similar to MR volumetry in assessing unilateral hippocampal sclerosis. MR volumetry of the hippocampus may not be needed for the evaluation of most cases of suspected hippocampal sclerosis.

Adolescent↗
PubMed1998

Drug eruption due to Bufferin showing erythema exsudativum multiforme with a photo-recall-like phenomenon.

A 21-year-old woman who had been taking several kinds of analgesics to treat dysmenorrhea developed episodic attacks of a purpuric macular eruption and a burning sensation on unexposed areas of the upper chest and back where she had sustained severe sunburn eight months earlier. Target-like lesions developed on these areas after intake of Bufferin, a combination of aspirin and dialuminate. After the eruptions had abated following systemic administration of a corticosteroid agent, a challenge test was performed, using a quarter of a tablet of Bufferin. The patient developed a temporary burning sensation and a erythematous color on the previously sunburned skin. We diagnosed this case as a drug eruption due to Bufferin showing erythema exsudativium multiforme with a photo-recall-like phenomenon. In our case, skin tests would be useful to confirm the causal drug.

Adult↗
PubMed1997

Genomic organization of the human DDX13 gene located between RD and RP1 in the class III MHC complex.

Recently we cloned a novel human cDNA homologous to yeast SKI2, reported a partial cDNA sequence, and mapped the gene to human chromosome 6p21 (Lee et al., 1995). It was a member of the DEAD/DExH family gene with seven conserved helicase domains; thus, it was named DDX13 consequently. We determined the complete genomic organization of the DDX13 gene. It consisted of 28 exons distributed over 11 kb of genomic DNA. An Alu element was present in introns 17 and 18, respectively. The major transcription start site was located 390 bp upstream from the translation initiation codon. The DDX13 gene was located in the class III region of the MHC between the genes coding for two other nuclear proteins, RD and RP1. The RD and DDX13 genes were oppositely oriented, and their first exons were overlapped. The distance between their first methionine codons was only 745 bp. It was of note that DDX13 and RD are in such proximity that their 5' regulatory regions overlap. The RP1 gene was located immediately downstream from the DDX13 gene in the same transcriptional orientation, and the distance between the stop codon of DDX13 and the translation initiation codon of RP1 was 2,272 bp.

Base Sequence↗
PubMed1997

Laminin chain-specific gene expression during mouse oocyte maturation.

Expression patterns of laminin chain mRNAs (A, B1, and B2) during mouse oocyte maturation were examined using the competitive reverse transcription-polymerase chain reaction (RT-PCR) method. Total and poly (A)-rich mRNAs isolated from various stages of maturing oocytes in vitro were subjected to RT-PCR and the precise amount of laminin chain-specific mRNA transcripts was estimated by adding externally known amounts of in vitro transcribed mutant cRNA transcripts as an internal control. The estimated copy numbers for A, B1, and B2 chain mRNAs in a single germinal vesicle-stage oocyte were 1.34 +/- 0.19 x 10(5), 6.95 +/- 0.32 x 10(6), and 2.0 +/- 0.56 x 10(5), respectively. Although notable changes of all laminin chain mRNA levels were not observed at any stage of meiotic maturation in total mRNA preparation, chain- and meiotic stage-dependent alterations of poly (A)-tailed mRNA quantities were observed in poly (A)-rich mRNA preparation. A potent RNA synthesis blocker, alpha-amanitin did not influence the changes of mRNA levels, implying the presence of posttranscriptional regulation mechanism in the expression of laminin chains during mouse oocyte maturation. Discrete and time-dependent deadenylation of A and B1 chain, but not B2 chain mRNA, was observed during oocyte maturation by a rapid amplification of cDNA ends (RACE)-PCR. In germinal vesicle (GV)-stage oocytes, only B1 chain was found to be present in a highly polyadenylated state and subsequent deadenylation was observed as meiosis progressed. The poly (A) tail modification was dependent on the initiation of meiotic resumption. Although all laminin chain mRNAs were found in fully grown and meiotically competent mouse oocytes, Western blot analysis detected the B1 chain polypeptide only in GV- and polar body (PB)-stage eggs. These results suggest that the expression of laminin B1 chain in mouse oocytes may be due to its large amount of mRNA transcripts and/or high level of polyadenylation state that is efficient for translational activation.

Animals↗