Search PubMed⌕ Search

Biomedical subjects

C W Lee

Publications and source records attributed to C W Lee.

At least 145 records · Page 8Linked to original sources
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

Synthesis and antitumor activity of 4-phenyl-1-arylsulfonyl imidazolidinones.

Novel 1-(1-benzoylindoline-5-sulfonyl)-4-phenyl-4,5-dihydroimidazolon es 3 synthesized show highly potent and broad cytotoxicities. Among them compound 3b (DW2143) exhibits much more potent cytotoxicities than doxorubicin and highly effective antitumor activities against murine (3LL, Colon 26) and human xenograft (NCI-H23, SW620) tumor models.

Animals↗
PubMed1998

Functional interplay between p53 and E2F through co-activator p300.

Both E2F and p53 are sequence specific transcription factors that regulate early cell cycle progression. The pathway of control mediated through E2F governs the transition from G1 into S phase whereas p53 in response to genotoxic stress can facilitate cell cycle arrest or apoptosis. The mechanisms which influence the outcome of p53 induction are not clear, although transcription of the p53 target gene, encoding the cdk-inhibitor p21(Waf1/Cip1), correlates with p53-mediated cell cycle arrest. Here using a combination of biochemical and functional assays we identify p300 as a co-activator required for p53-dependent transcriptional activation of Waf1/Cip1. Furthermore, we show that the cdk-inhibitor p21(Waf1/Cip1) autoregulates in a positive fashion transcription through modulating the activity of the p53/p300 complex, whilst negatively regulating the activity of E2F by preventing cdk-dependent phosphorylation of pRb. Consistent with a role for p21(Waf1/Cip1) in the autoregulation of p53-dependent transcription, p300 augments the ability of p53 to cause G1 arrest and, conversely, cells undergoing p53-dependent apoptosis are rescued by p300. Thus, our data suggest that the ability of p300 to interact with p53 influences the physiological consequence of p53 activation. From previous studies it is known that cells expressing aberrant levels of E2F-1 can undergo p53-dependent apoptosis. In addition, we find that E2F-1 can cause apoptosis in p53-/- tumour cells and further p300, which also functions as a co-activator for the E2F/DP heterodimer, enhances the apoptotic activity of E2F-1. In conditions where E2F-1 and p53 co-operate in apoptosis E2F-1 can effectively compete for p300, causing a reduction in p53-dependent transcription. Thus, a functional interaction between p300 and either p53 or E2F-1 has a profound impact on early cell cycle progression, specifically in regulating the contrasting outcomes of cell cycle arrest and apoptosis. These results suggest a critical role for p300 in integrating and co-ordinating the functional interplay between the pathways of growth control mediated by E2F and p53.

Binding Sites↗
PubMed1998

Clinicopathological significance of altered loci of replication error and microsatellite instability-associated mutations in gastric cancer.

Replication errors (RERs) judged by microsatellite instability and its associated mutations have been recognized as an important mechanism in tumorigenesis of gastric cancers (GCs). To gain a deeper insight into its significance, we examined the frequency of RERs using nine microsatellite markers and screened mutations in the polydeoxyadenine tract of the transforming growth factor beta type II receptor gene (TGF-betaRII) and polydeoxyguanine tracts of insulin-like growth factor II receptor and BAX genes. Twenty-four (30%) of 80 patients with GC had RERs, of which 3, 8, and 13 had one, two, and three or more loci, respectively. In 13 tumors with RERs in three or more loci, frameshift mutations of TGF-betaRII, insulin-like growth factor II receptor, and BAX were identified in 12, 3, and 2, respectively. Compared with GC with none, one or two RER-positive loci as a group, GC with RERs in three or more loci showed a significantly higher frequency of antral location (12 of 13 versus 35 of 67; P = 0.01), intestinal subtype (11 of 13 versus 30 of 67; P = 0.01), and previous Helicobacter pylori infection (12 of 13 versus 41 of 67; P = 0.05) and a lower incidence of lymph node metastasis (5 of 13 versus 49 of 67; P = 0.02) and tended to be in an advanced stage (12 of 13 versus 54 of 67; P = 0.28). These data indicate that GC with multiple RERs manifest distinct clinicopathological characteristics, and that a high frequency of frameshift mutations involving the TGF-betaRII gene may be causatively linked with tumorigenesis and progression.

Adult↗
PubMed1998

Characteristic immunostimulation by angelan isolated from Angelica gigas Nakai.

The immunopharmacological characteristics of angelan, a polysaccharide purified from Angelica gigas Nakai, were investigated in relation to the specificity to immune cells. The treatment of angelan increased the expression of IL-2, IL-4, IL-6, and IFN-gamma. The expression of IL-6 and IFN-gamma was rapidly augmented but that of IL-2 responded later. In the case of IL-4, angelan stimulated at early time after exposure but down-regulated thereafter. These results suggested that macrophages and natural killer cells involved in nonspecific immunity were primarily activated and helper T cells were secondarily affected by angelan. Angelan also had lympho-proliferative potential to B cells, specifically. The specificity of angelan was also elucidated in a cell fractionation experiment. The activated B cells by angelan also increased antibody production. The direct activation of B cells, macrophages, and accessory cells and the indirect activation of helper T cells coordinately increased immune functions such as in vitro and in vivo T-dependent immunization and antibody production. The experiment of host resistance to syngeneic tumors also showed that angelan potentiated the immune functions. In conclusion, angelan, a purified polysaccharide from an oriental herbal drug, showed characteristic immunostimulation, which was different from clinically used polysaccharides such as lentinan and PSK.

Adjuvants, Immunologic↗
PubMed1998

Stenting of unprotected left main coronary artery stenoses: immediate and late outcomes.

OBJECTIVES: We examined the immediate and long-term outcomes after stenting of unprotected left main coronary artery (LMCA) stenoses in patients with normal left ventricular (LV) function. BACKGROUND: Left main coronary artery disease is regarded as an absolute contraindication for coronary angioplasty. Recently, several reports on protected or unprotected LMCA stenting, or both, suggested the possibility of percutaneous intervention for this prohibited area. METHODS: Forty-two consecutive patients with unprotected LMCA stenoses and normal LV function were treated with stents. The post-stent antithrombotic regimens were aspirin and ticlopidine; 14 patients also received warfarin. Patients were followed very closely with monthly telephone interviews and follow-up angiography at 6 months. RESULTS: The procedural success rate was 100%, with no episodes of subacute thrombosis regardless of anticoagulation regimen. Six-month follow-up angiography was performed in 32 of 34 eligible patients. Angiographic restenosis occurred in seven patients (22%, 95% confidence interval 7% to 37%); five patients subsequently underwent elective coronary artery bypass graft surgery (CABG), and two patients were treated with rotational atherectomy plus adjunct balloon angioplasty. The only death occurred 2 days after elective CABG for treatment of in-stent restenosis. The other patients (without angiographic follow-up) remain asymptomatic. CONCLUSIONS: Stenting of unprotected LMCA stenoses may be a safe and effective alternative to CABG in carefully selected patients with normal LV function. Further studies in larger patient populations are needed to assess late outcome.

Angioplasty, Balloon↗
PubMed1998

A survey of practice in management of malignant ascites.

The purpose of this study was to determine physicians' attitudes toward and preferences for palliative management of malignant ascites. A random sample of eighty physicians practicing in Canada was selected from the memberships of the Canadian Association of Medical Oncologists, the Canadian Association of Gastroenterology, the Canadian Society of Palliative Care Physicians, and the Society of Gynecologic Oncologists of Canada. Physicians were questioned on their use of different modalities in management of malignant ascites, and preferences based on attitudes toward efficacy of various treatments. Eighty surveys were mailed, with a second mailing, followed by telephone contact. The response rate was 76% (59/78), with two potential respondents deemed ineligible. Among the 44 physicians who treat malignant ascites, paracentesis is employed by 43 (98%), and felt to be effective by 39 (89%). Diuretics are used by 61% (27/44), although fewer feel diuretics are effective management (20/44, 45%). Peritoneovenous shunts, dietary measures, and other modalities are used less frequently than either paracentesis or diuretics. The most commonly used means of managing malignant ascites is paracentesis, which is also felt to be the most effective by the group surveyed. After paracentesis, diuretics and peritoneovenous shunting are used most frequently, but there is no apparent consensus as to their effectiveness. Managing malignant ascites remains problematic, and we propose further study of management strategies to clarify the role of various treatments.

Adult↗
PubMed1998

Localized mucosal involvement and severe pulmonary involvement in a young patient with paraneoplastic pemphigus associated with Castleman's tumour.

We describe a 19-year-old female patient who developed recurrent ulcerations limited to the orogenital mucosa for the last 3 years. She also developed dyspnoea 5 months after the onset of the orogenital lesions. Castleman's tumour of the retroperitoneum was found incidentally during routine physical examination. The diagnosis of paraneoplastic pemphigus (PNP) was made by pathological and immunological studies. The orogenital ulceration responded well to corticosteroid therapy, but severe bronchiolitis obliterans progressed despite intensive care. The patient eventually died from respiratory failure. This case demonstrates the diversity of clinical features of paraneoplastic pemphigus.

Adult↗
PubMed1998

Effects of percutaneous balloon mitral valvuloplasty and exercise training on the kinetics of recovery oxygen consumption after exercise in patients with mitral stenosis.

AIMS: Kinetics of recovery oxygen consumption after exercise plays an important role in determining exercise capacity. This study was performed to assess the kinetics of recovery oxygen consumption in mitral stenosis and evaluate the effects of percutaneous balloon mitral valvuloplasty and exercise training on the kinetics. METHODS AND RESULTS: Thirty patients with mitral stenosis (valve area < or =1.0 cm2) and same sized age- and size-matched healthy volunteers were included for this study. All subjects performed maximal upright graded bicycle exercise. Thirty consecutive patients who underwent successful percutaneous balloon mitral valvuloplasty (valve area > or =1.5 cm2 and mitral regurgitation grade < or =2), were randomized to an exercise training group or non-training group. The exercise group performed daily exercise training for 3 months. Half-recovery time of peak oxygen consumption was significantly delayed in mitral stenosis as compared to normal subjects (120+/-42 s vs 59+/-5, P<0.01). Peak oxygen consumption (ml x min(-1) x kg(-1)) was significantly increased in both the training (16.8+/-4.9 to 25.3+/-6.9) and non-training groups (16.3+/-5.1 to 19.6+/-6.0) 3 months after percutaneous balloon mitral valvuloplasty. Half-recovery time of peak oxygen consumption was significantly shortened in the training group (124+/-39 to 76+/-13, P<0.01), but not in the non-training group (114+/-46 to 109+/-44 s, P=0.12) at 3 months follow-up. The degrees of symptomatic improvement after percutaneous balloon mitral valvuloplasty were more closely correlated with the changes of the half-recovery time of peak oxygen consumption than those of peak oxygen consumption. CONCLUSION: Kinetics of recovery oxygen consumption was markedly delayed in mitral stenosis, which was improved after exercise training but not after percutaneous balloon mitral valvuloplasty alone. These results suggest that adjunctive exercise training may be useful for improvement of recovery kinetics and subjective symptoms after percutaneous balloon mitral valvuloplasty.

Adult↗
PubMed1998

Holmium laser lithotripsy for ureteral calculi: an outpatient procedure.

A retrospective review was conducted to evaluate the efficacy of ureteroscopic lithotripsy using the holmium laser with a semirigid endoscope in a newly established day surgery center. In 1996, 69 consecutive patients (40 male and 29 female) with a mean age of 46.7 (range 21-73) years and ASA status I or II underwent ureteroscopic lithotripsy for their ureteral calculi using the holmium laser (365-micron fiber; power setting 0.5-1.4 J/5 Hz) and 8.5F semirigid ureteroscope in a day surgery setting. Stone features, postoperative pain scores, readmissions, and complications were evaluated. Eighteen upper, 17 middle, and 34 lower ureteral stones were treated, with a mean size measuring 12.1 (5-45) mm. The mean operative time was 61 minutes including the anesthetic time (range 15-150 minutes), and the success rate was 91% (63/69). The complication rate was 10% (7/69) including four unscheduled readmissions (6%). Telephone follow-up on postoperative Day 1 and Day 3 revealed mean pain scores of 2 and 1, respectively (on a 0-10 scale) and an analgesic requirement of 1 tablet of Dologesic (containing 32.5 mg of dextropropoxyphene + 320 mg of paracetamol) four times a day on both days. Ureteroscopic lithotripsy using the holmium laser and a semirigid endoscope is highly successful and well tolerated and carries a low complication rate. It is indicated as an ambulatory and minimally invasive treatment modality in low-risk patients with ureteral stones.

Adult↗
PubMed1998

Safety, tolerability and pharmacokinetics of the new long-acting quinolone DW-116 after single and multiple dosing in healthy subjects.

The safety, tolerability and pharmacokinetics of DW-116, a new fluoroquinolone with a broad antibacterial spectrum, were evaluated in healthy male subjects after administration of single oral doses of 100, 200, 300 and 800 mg and after administration of multiple oral doses of 300 or 400 mg, respectively, for 7 days. DW-116 was well tolerated. Gastrointestinal symptoms and skin reactions were noted and considered to be possibly related to DW-116. The geometric means of the maximum plasma concentrations (Cmax) linearly increased with the dose administered from 1.19 mg/L to 8.73 mg/L after single dose administration. At steady state, the geometric mean minimum and maximum plasma concentrations were 2.14 and 5.65 mg/L, respectively, after the multiple 300 mg dose and 2.73 and 8.00 mg/L, respectively, for the multiple 400 mg dose. Tmax varied between 1 and 5 h. The terminal half-life ranged from 11.37 to 24.89 h. The geometric mean renal clearance was approximately 30 mL/min. Approximately 45% of the dose was excreted unchanged in urine within 60 h. There was no clinically relevant deviation from dose proportionality. The changes in steady-state pharmacokinetic parameters when DW-116 was taken before a high-fat breakfast were not clinically relevant. In conclusion, DW-116 was safe in this study, the first administration to human subjects. Its pharmacokinetics indicate that once-daily dosing may be possible.

Adult↗
PubMed1998

Induction of protective immunity in chickens vaccinated with infectious bronchitis virus S1 glycoprotein expressed by a recombinant baculovirus.

A recombinant baculovirus containing the S1 glycoprotein gene of the virulent nephropathogenic KM91 strain of infectious bronchitis virus (IBV) was constructed in order to investigate protective immunity in vaccinated chickens. Results from the protection test were evaluated by re-isolation of virus from the kidneys and tracheas of vaccinated chickens after challenge with strain KM91. After three immunizations, the recombinant S1 (rS1) glycoprotein induced 50% protection of the kidney, whilst inactivated KM91 induced 88% and 50% protection of the kidney and trachea, respectively. In chickens primed with the attenuated H120 vaccine strain, which is heterologous to KM91, the rS1 glycoprotein induced 83% protection of the kidney after two immunizations. Haemagglutination-inhibition titres were also increased in chickens immunized with the rS1 glycoprotein after three immunizations, and significantly higher titres were detected after challenge. These data indicate that the expressed rS1 glycoprotein alone can induce a protective immune response as well as an antibody response.

Animals↗
PubMed1998

Figurate purpuric eruptions on the trunk: acetaminophen-induced rashes.

A 23-year-old man had recurrent erythematous purpuric patches in a transverse-linear arrangement on his back and arms. One week prior to a recent episode, he took acetaminophen for 3 days. Four months earlier, he developed the same purpuric lesions at/around the same anatomical site when he took acetaminophen for pain-relief. A biopsy specimen showed capillaritis and extravasation of erythrocytes in the papillary dermis. A provocation test with acetaminophen confirmed these lesions as drug-induced rashes. The uncommon topographic and morphologic features of the purpuric lesion in this patient might be considered as an unusual expression of pigmented purpuric dermatosis caused by acetaminophen.

Acetaminophen↗
PubMed1998

Development of PCR assays for species- and type-specific identification of Pasteurella multocida isolates.

Genomic subtractive hybridization of closely related Pasteurella multocida isolates has generated clones useful in distinguishing hemorrhagic septicemia-causing type B strains from other P. multocida serotypes. Oligonucleotide primers designed during the sequencing of these clones have proved valuable in the development of PCR assays for rapid species- and type-specific detection of P. multocida and of type B:2 in particular. This study demonstrated that the primer pair designed from the sequence of the clone 6b (KTT72 and KTSP61) specifically amplified a DNA fragment from types B:2, B:5, and B:2,5 P. multocida and that the primers KMT1T7 and KMT1SP6 produced an amplification product unique to all P. multocida isolates analyzed. It was also shown that PCR amplification performed directly on bacterial colonies or cultures represents an extremely rapid, sensitive method of P. multocida identification.

Base Sequence↗
PubMed1998

HLA class II allele associations in Korean patients with pemphigus.

BACKGROUND: Studies at the population level have demonstrated associations between pemphigus (pemphigus vulgaris, PV, and pemphigus foliaceus, PF) and particular HLA haplotypes, which suggests that there may be a genetic predisposition for the disease. OBJECTIVE/METHODS: The aim of the present study was to examine the distribution/frequency pattern of HLA class II alleles (DRB1, DQA1 and DQB1) from a group of 30 Korean patients with pemphigus (15 PV and 15 PF) by PCR amplification with sequence-specific primers. RESULTS: In PV, the frequency of DRB1*01 allele was found to be significantly high (pc = 0.0014); in PF, DRB1*01, DQA1*0302 and DQB1*0603 alleles showed positive associations with statistical significances (pc = 0.0002, 0.0007 and 0.0067, respectively), when compared with those found in Korean controls. CONCLUSIONS: In this small-sample study, findings of allelic frequencies among Korean patients with pemphigus are somewhat different from those found in other populations.

Alleles↗
PubMed1998

Arthritic manifestations of inflammatory bowel disease.

Inflammatory bowel disease (IBD) is commonly associated with arthritic manifestations. They are divided into three clinical categories; peripheral arthritis, spondylitis, and sacroiliitis. To evaluate the incidence of arthritis associated with IBD in Korea, we retrospectively reviewed one hundred and twenty-nine patients with IBD, 77 with ulcerative colitis (UC) and 52 with Crohn's disease (CD). Arthritis occurred in twenty-two patients (17.1%); 15 with UC(19.6%), 7 with CD (13.5%). Patients with arthritis had more active inflammations and all were seronegative except one patient. Peripheral arthritis was found in twenty patients (15.5%) and more common in UC (19.6%) than in CD (9.6%). Joint involvements tended to be monoarticular or pauciarticular, and most frequently developed in the knee and ankle. Spondylitis was diagnosed in one patient (1.6%) who showed HLA B27 positivity. Radiographic sacroiliitis was observed in eight patients (6.2%) who revealed HLA B27 negativity. Both peripheral arthritis and sacroiliitis were found in six patients (4.6%). In CD, arthritis occurred in 20% of the patients with colonic involvement but in none of the patients without colonic involvement. In conclusion, arthritis was frequent in patients with IBD. Peripheral arthritis was more common in patients with UC than CD. All the patients with CD and arthritis had colonic involvement.

Adult↗