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Y B Kim

Publications and source records attributed to Y B Kim.

At least 127 records · Page 7Linked to original sources
PubMed1998

Workshop studies with monoclonal antibodies identifying a novel porcine differentiation antigen, SWC9.

Two monoclonal antibodies (mAb) within cluster M4 of the myeloid section of the Second International Swine CD Workshop, C4 (No. 144) and PM18-7 (No. 192), showed reactivity with thymocytes and among cells of myelomonocytic origin with mature macrophages but not with monocytes and granulocytes. Both mAb recognize a protein showing two bands of 205 kDa and 130 kDa under both reducing and non-reducing conditions. Although epitope mapping with these mAb could not be performed, this cluster received the SWC9 designation.

Animals↗
PubMed1998

Phylogenetic analysis of the nef gene reveals a distinctive monophyletic clade in Korean HIV-1 cases.

To study the genetic variation of the HIV-1 strains prevalent in South Korea, we analyzed the nef sequences derived from 46 HIV-1-positive individuals living in various geographic regions in Korea. Phylogenetic analysis revealed four subtypes of HIV-1: A (3 patients), B (41 patients), D (1 patient), and a type that could not be clearly classified to any known subtype (1 patient). Thirty-five of the 41 Korean subtype B isolates formed a distinct monophyletic clade that is not related to any of the international sequences from the Los Alamos Database or GenBank as of June 1997. Indeed, the presence of unique conserved sequences was identified among the Korean isolates in this Korean subtype B group. The variations in the nucleotide sequences of a majority (32 of 35) subtype B samples within the Korean clade were 1.9% to 8.8%, and amino acid sequences varied from 3.9% to 15.5%. These results suggest that HIV-1 strains currently present in South Korea might have originated from a few sources or might be developing through a certain selective pressure. This is the first report on the molecular nature of the HIV-1 infection present in South Korea.

Adolescent↗
PubMed1998

Does hysteroscopy improve upon the sensitivity of dilatation and curettage in the diagnosis of endometrial hyperplasia or carcinoma?

OBJECTIVE: The objective of this study was to determine whether hysteroscopy improved upon the diagnostic sensitivity of dilatation and curettage (D+C) in the detection of endometrial hyperplasia and carcinoma. METHODS: A retrospective chart review was conducted of all patients undergoing hysteroscopy/D+C for abnormal uterine bleeding between 1991 and 1995. Hysteroscopic impressions and D+C diagnoses were compared. RESULTS: Three hundred seventy-three patients were included in the study. Of the 61 patients with D+C demonstrating hyperplasia, the hysteroscopic impression was hyperplasia in 32 (52%). Of the 10 patients with D+C demonstrating carcinoma, the hysteroscopic impression was hyperplasia in 8 (80%) and carcinoma in 2 (20%). Two additional cases of carcinoma were diagnosed within 6 months of hysteroscopy/D+C, and both had been missed on both hysteroscopy and D+C. Of 204 patients with a normal hysteroscopic impression, 23 (11%) had hyperplasia on D+C. CONCLUSIONS: Hysteroscopy did not improve upon the sensitivity of D+C in the detection of endometrial hyperplasia or carcinoma.

Adult↗
PubMed1998

Diagnostic and therapeutic advances in gynecologic oncology: screening for gynecologic cancer.

Endometrial carcinoma is associated with a good prognosis because patients tend to present with early disease. Mass screening is therefore unlikely to be of benefit. High-risk populations may benefit from screening, but no prospective studies have demonstrated a benefit in any population. The most promising modality for screening appears to be TVS, and a normal TVS may also preclude the need for further evaluation of symptomatic patients. The appropriate use of TVS in patients on tamoxifen is currently unknown. Hysteroscopy and endometrial biopsy may have a role in the evaluation of symptomatic patients but do not appear promising as screening modalities.

Biomarkers, Tumor↗
PubMed1998

Incidence and predictors of cervical dysplasia in patients with minimally abnormal Papanicolaou smears.

OBJECTIVE: To estimate the incidence of dysplasia in patients with Papanicolaou smears showing atypical squamous cells of undetermined significance (ASCUS) and low-grade squamous intraepithelial lesions (SIL) and to identify clinical predictors of dysplasia in these patients. METHODS: Patients referred for ASCUS and low-grade SIL were reviewed retrospectively. All patients were evaluated with immediate colposcopy. A multivariate logistic regression analysis was performed to identify clinical predictors of histologic SIL and histologic high-grade SIL. RESULTS: One hundred thirty-seven (34%) of 406 consecutive patients had histologic SIL. Regression analysis identified age (under 35 versus 35 years or above) and initial smear (low-grade SIL versus ASCUS) as statistically significant predictors of histologic SIL and high-grade SIL (P < .001). When patient outcomes were analyzed by age and initial Papanicolaou smear results, the subgroup of patients 35 years or older with ASCUS had low incidences of histologic SIL (14%) and high-grade SIL (1%). The other subgroups (under 35 years with ASCUS, under 35 years with low-grade SIL, and 35 years or older with low-grade SIL) had incidences of histologic SIL and histologic high-grade SIL of at least 28% and 14%, respectively. CONCLUSION: The high incidence of dysplasia in patients with minimally abnormal Papanicolaou smears suggests that immediate colposcopy might be appropriate for many of these patients. Age and initial Papanicolaou smear are predictive of dysplasia and might be used to select patients who have low incidence of dysplasia and might not require immediate colposcopy.

Adult↗
PubMed1998

Detection of Escherichia coli O157:H7 in the beef marketed in Malaysia.

Twelve strains of Escherichia coli O157:H7 were isolated from 9 of 25 beef samples purchased from retail stores in Malaysia. These strains produced Shiga toxin 2 with or without Shiga toxin 1 and had the eae gene and a 60-MDa plasmid. The antibiograms and the profiles of the arbitrarily primed PCR of the strains were diverse, suggesting that the strains may have originated from diverse sources.

Animals↗
PubMed1998

The protective effects of lactoferrin feeding against endotoxin lethal shock in germfree piglets.

The unique germfree, colostrum-deprived, immunologically "virgin" piglet model was used to evaluate the ability of lactoferrin (LF) to protect against lethal shock induced by intravenously administered endotoxin. Piglets were fed LF or bovine serum albumin (BSA) prior to challenge with intravenous Escherichia coli lipopolysaccharide (LPS), and temperature, clinical symptoms, and mortality were tracked for 48 h following LPS administration. Prefeeding with LF resulted in a significant decrease in piglet mortality compared to feeding with BSA (16.7 versus 73.7% mortality, P < 0.001). Protection against the LPS challenge by LF was also correlated with both resistance to induction of hypothermia by endotoxin and an overall increase in wellness, as quantified by a toxicity score developed for these studies. In vitro studies using a flow cytometric assay system demonstrated that LPS binding to porcine monocytes was inhibited by LF in a dose-dependent fashion, suggesting that the mechanism of LF action in vivo may be inhibition of LPS binding to monocytes/macrophages and, in turn, prevention of induction of monocyte/macrophage-derived inflammatory-toxic cytokines.

Animals↗
PubMed1998

A novel Alcian yellow-toluidine blue (Leung) stain for Helicobacter species: comparison with standard stains, a cost-effectiveness analysis, and supplemental utilities.

Helicobacter pylori (Hp) gastritis is a worldwide problem significantly associated with duodenal and gastric peptic ulcer disease, gastric carcinomas, and MALT-type lymphomas. A simple, rapid, reproducible, reliable, and inexpensive stain to detect the organism in gastric biopsy specimens is thus of great value. To assess the reliability and cost-effectiveness of a novel Alcian yellow-toluidine blue (Leung) stain for Hp, we stained 60 endoscopic mucosal biopsy specimens from patients with Hp gastritis and measured time to detection of organism, Hp numbers (scale, 1-5), and technical costs. We also stained serial 5-microm step sections of 17 of these cases with the Giemsa and modified Steiner (MS) methods, and similar measurements were made. Also, specimens from various normal gastrointestinal sites and metaplastic lesions, as well as four cases each of giardiasis and cryptosporidiosis, were stained with the Leung method. In the subset of 17 cases, the Leung stain enhanced detection time and compared favorably with the Giemsa method, though the MS method was somewhat superior. Hp scores were similar among all groups. Mean time to detection and Hp scores were similar in the larger (n = 60) group stained with hematoxylin and eosin and the Leung stain. Material costs and technologist's time for Giemsa stains, however, were greater than for the Leung stain, and technologist's time for MS was nearly fourfold that of the Leung stain. With the Leung method, mucus from all gastrointestinal sites and metaplastic lesions stained yellow, and this stain provided excellent contrast and morphologic definition in giardiasis and cryptosporidiosis. We suggest that the newly developed Alcian yellow-toluidine blue (Leung) histochemical stain is a good choice as the standard for routine Hp staining because it is the cheapest and easiest to prepare and because pathologists' detection with this stain compares favorably with detection times achieved with more traditional and established methods.

Coloring Agents↗
PubMed1998

A new treatment for syringoma. Combination of carbon dioxide laser and trichloroacetic acid.

BACKGROUND: Although syringoma represents a benign tumor of skin appendage, multiple and diffuse facial lesions can cause cosmetic problems for the affected individuals. Scarring, recurrence and postinflammatory hyperpigmentation can be serious troubles, especially for oriental people receiving various therapeutic modalities. OBJECTIVE: The purpose of this study was to evaluate the histopathologic and clinical efficacy of a new therapeutic approach for syringoma, consisting of combination of carbon dioxide (CO2) laser and 50% trichloroacetic acid (TCA). METHODS: Eighty skin biopsy specimens (45 patients) were evaluated to determine the depth of syringoma lesion. Among these, 28 specimens were obtained after a single test-pulse of CO2 laser (focused, superpulsed mode, power setting of 0.7-2 watts, beam diameter of 0.1 mm, pulse duration of 0.1 seconds), and 3 specimens after one pass of CO2 laser and 50% TCA. The depths of laser-induced vaporization and TCA-induced tissue necrosis were measured. Twenty patients were treated with the combination therapy of CO2 laser (two passes of laser) and 50% TCA. Clinical effectiveness and complications of combination therapy were evaluated by direct observation and photographs. RESULTS: Tumor depth: Analysis of eight specimens revealed tumor depth of 0.70 +/- 0.20 mm (mean +/- SD), ranging from 0.4-1.2 mm. There were no correlations between tumor depth and age of onset or duration of the tumor. Laser penetration depth: CO2 laser irradiation, 0.7-2 watts, induced vaporization of 0.29 +/- 0.12 mm in depth with carbonized rim of 0.1 +/- 0.03 mm width (n = 28 from 15 patients). With laser power of 1 watt, vaporization ranged from 0.17-0.45 mm in depth. Laser and TCA induced necrosis: TCA application resulted in extra tissue necrosis of 0.22-0.25 mm in depth beyond the level achieved by laser vaporization. CLINICAL FINDINGS: Among the 20 patients treated with the combination therapy, therapeutic effect for 11 patients was excellent, 6 patients showed good clinical response, and 3 patients were fair. There were no serious complications resulting from this procedure such as infection, scarring or textural change. CONCLUSION: The application of 50% TCA after CO2 laser irradiation was effective for removing deep-seated syringoma cells and for reducing the side effects, especially scarring. To the best of our knowledge, this is the first study introducing the combination of CO2 laser and TCA for removal of syringoma.

Adolescent↗
PubMed1997

Phenotype of porcine monocytic cells: modulation of surface molecule expression upon monocyte differentiation into macrophages.

When porcine blood monocytes differentiate in vitro into macrophages, their morphology, as well as side scatter and forward scatter measured by flow cytometry, changed in a manner similar to that with human cells. During this differentiation, the initial high expression of CD molecules on porcine monocytes was down-regulated, with one exception--SWC9. Freshly isolated blood monocytes were SWC9-, but after culture the cells had become SWC9+. Thus, porcine monocytes were characterised as SWC3+SWC9-CD14high; macrophages were SWC3+SWC9+CD14low, the latter also displaying a down-regulation of CD11a/18, and, to a lesser degree, CD44. Both SWC9-CD14high monocytes and SWC9+CD14low macrophages were identifiable in freshly prepared monocytic cells from the spleen. Alveolar macrophages, on the other hand, were dominated by SWC9+CD14low cells, similar in phenotype to in vitro monocyte-derived macrophages. The consequences which these results have for studies on virus infections of porcine monocytic cells are discussed.

Animals↗
PubMed1997

Progestin alone as primary treatment of endometrial carcinoma in premenopausal women. Report of seven cases and review of the literature.

BACKGROUND: The standard treatment for endometrial carcinoma is staging laparotomy with total abdominal hysterectomy and bilateral salpingo-oophorectomy. In an attempt to preserve childbearing potential, selected patients with endometrial carcinoma were treated with progestin alone as primary therapy. METHODS: Patients were identified through searches of tumor registries and solicitation of consulting gynecologic oncologists at the affiliated institutions of the University of California-Los Angeles Center for the Health Sciences. Only those patients with a diagnosis of endometrial carcinoma treated with progestin alone as primary therapy were included in the study. Independent pathologic review was performed by a recognized expert gynecologic pathologist to exclude cases of endometrial hyperplasia. A MEDLINE search was conducted to identify reports of similarly treated patients. RESULTS: Seven patients were treated with progestin alone for endometrial carcinoma at the study institution. Fourteen additional patients were identified through the literature search. Combining the data for all patients, 13 of 21 patients (62%) had an initial response to progestins. Three initial responders later developed recurrent disease, one of whom was found to have extrauterine disease at laparotomy. Eight of 21 patients (38%) did not respond to progestins and underwent more definitive treatment. None of these patients later developed recurrent disease. Six viable infants were delivered of three patients after therapy. Nineteen of 21 patients were alive without evidence of disease at last follow-up. CONCLUSIONS: The results of this study show that premenopausal women with endometrial carcinoma may be treated successfully with progestin therapy alone as primary therapy to preserve childbearing potential.

Adenocarcinoma↗
PubMed1997

Heparin coating of vascular prostheses reduces thromboemboli.

BACKGROUND: Synthetic conduits made from currently available materials are suboptimal for use in small-diameter vascular reconstruction because of their high surface thrombogenicity, which leads to failure. METHODS: In this study control, heparin-irrigated, or heparin-bonded expanded polytetrafluoroethylene (ePTFE) grafts (4 mm long by 1 mm inner diameter) were implanted to reconstruct the iliac artery in male rats. The cremaster muscle was isolated as an island flap based on branches of the iliac artery downstream from the graft. Emboli were quantitated by using intravital fluorescent microscopy of the cremaster muscle's microcirculation. RESULTS: The mean number of emboli observed per animal during a 20-minute period was 91 for the control group, 84 for the heparin-irrigated group, and 22 for the tridodecylmethylammonium chloride (TDMAC)-heparin group. The mean area of each embolus was 1057 microns 2 for control, 940 microns 2 for heparin-irrigated, and 808 microns 2 for TDMAC-heparin-coated grafts (p < 0.05 for TDMAC-heparin versus control or heparin-irrigated). CONCLUSIONS: A TDMAC-heparin coating of ePTFE microvascular prostheses significantly reduces downstream microemboli.

Animals↗
PubMed1997

Interaction of divalent metal ions with Zn(2+)-glycerophosphocholine cholinephosphodiesterase from ox brain.

The effect of divalent metal ions on the activity of glycerophosphocholine cholinephosphodiesterse from ox brain was examined. Zn(2+)- and Co(2+)-glycerophosphocholine cholinephosphodiesterases were prepared from the exposure of apoenzyme to Zn2+ and Co2+, respectively, and the properties of two metallo-phosphodiesterases were compared to those of native phosphodiesterase. Although two metallo-enzymes were similar in expressing Km value, optimum pH or sensitivity to Cu2+, they differed in the susceptibility to the inhibition by thiocholine or tellurite; while Co(2+)-phosphodiesterase was more sensitive to tellurites, Zn(2+)-phosphodiesterase was more susceptible to inhibition by thiocholine. In addition, Zn(2+)-phosphodiesterase was more thermo-stable than Co2+ enzyme. Separately, when properties of native phosphodiesterase were compared to those of each metallo-phosphodiesterase, native phosphodiesterase was found to be quite similar to Zn(2+)-phosphodiesterase in many respects. Even in thermo-stability, native enzyme resembled Zn(2+)-phosphodiesterase rather than Co(2+)-enzyme. Consistent with this, the stability of native phosphodiesterase was maintained in the presence of Zn2+, but not Co2+, Mn2+ was also as effective as Zn2+ in the stabilization of the enzyme. Noteworthy, the native enzyme was found to be inhibited competitively by Cu2+ with a Ki value of 20 microM, and its inhibitory action was antagonized effectively by Zn2+ or Co2+. Also, choline, another competitive inhibitor of the enzyme, appeared to antagonize the inhibitory action of Cu2+. Taken together, it is suggested that there may be multiple binding sites for divalent metal ions in the molecule of glycerophosphocholine cholinephosphodiesterase.

Animals↗
PubMed1997

Note: purification of amylase secreted from Bifidobacterium adolescentis.

Bifidobacterium adolescentis Int-57 isolated from human faeces produced extracellular amylase. The enzyme was purified from the culture supernatant fluids by ammonium sulphate precipitation, gel-filtration chromatography (Sephadex-G-75), ion-exchange chromatography (CM-cellulose) and FPLC. SDS-PAGE of the purified enzyme revealed a major band with an apparent molecular weight of 66 kDa. The pI was 5.2. Enzyme activity was optimal at 50 degrees C, and at pH 5.5. The enzyme was stable at 20-40 degrees C, and at pH 5-6 with a K(m) value of 2.4 g l-1 soluble starch. The activation energy was 42.3 kJ mol-1. The enzyme was significantly inhibited by maltose (10%), glucose (10%), Cu2+ (5 mmol l-1), Zn2+ (5 mmol l-1), N-bromosuccinimide (5 mmol l-1), EDTA (5 mmol l-1), I2 (1 mmol l-1) and activated by beta-mercaptoethanol (10 mmol l-1).

Amylases↗
PubMed1997

Sustained release of antibiotic from a fibrin-gelatin-antibiotic mixture.

To improve the therapeutic effect of antibiotics in the ear cavity postoperatively, a fibrin- and gelatin-based drug delivery system was designed and in vitro efficacy was evaluated. Four kinds of fibrin clot were made from ampicillin, gentamicin, and ofloxacin, and biologic assay was performed using Bacillus subtilis. The fibrin-gelatin-gentamicin mixture demonstrated antibiotic activity for up to 120 hours against B subtilis. Gentamicin was found to be released more slowly from the fibrin-gelatin mixture than from the fibrin mixture in this experiment. These results suggest that this device can be clinically used in a limited field such as postoperative care of ear infection.

Administration, Topical↗
PubMed1997

Helicobacter pylori infection and the risk of gastric cancer among the Korean population.

Helicobacter pylori infection has been associated with chronic atrophic gastritis, a precursor of gastric cancer. We conducted a prospective, case-controlled study to investigate whether H. pylori infection increases the risk of gastric cancer in Korean people with a high risk of gastric cancer. We enrolled 160 gastric cancer patients who were confirmed by endoscopic biopsy during 1994 and 160 age-matched control subjects with non-ulcer dyspepsia were compared to document the relationship between H. pylori infection and gastric cancer. The presence of H. pylori infection was determined by the rapid urease test and/or histology by Wright-Giemsa staining. The overall presence of H. pylori infection was 60% in gastric cancer patients and 51.9% in age-matched control subjects (odds ratio 1.39; 95% confidence interval 0.894-2.17; P = 0.143). Carcinomas of cardia, body and antrum were not associated with H. pylori infection (odds ratio 1.43, 1.69 and 1.29, respectively; 95% confidence interval, 0.271-7.52, 0.787-3.62 and 0.689-2.43, respectively; P = 0.178, 0.177 and 0.642, respectively) nor was the intestinal or diffuse type of cancer (odds ratio 1.39 and 1.40, respectively; 95% confidence interval 0.791-2.45 and 0.681-2.87, respectively; P = 0.250 and 0.835, respectively). Gender was not a risk for gastric cancer. In contrast to previous studies, these results do not provide evidence of H. pylori infection for gastric carcinogenesis in Korea.

Adenocarcinoma↗
PubMed1997

Co-existing gastric cancer and duodenal ulcer disease: role of Helicobacter pylori infection.

BACKGROUND: The association of gastric cancer and chronic duodenal ulcer disease is considered rare. In fact duodenal ulcer disease is believed to somehow "protect" against the development of gastric cancer. Helicobacter pylori infection is an important factor in the development of gastric cancer. No detailed investigation on the prevalence of H. pylori in coexistence of gastric cancer and duodenal ulcer disease has been performed. We evaluated the frequency of H. pylori infection in the patients with co-existence of gastric cancer and duodenal ulcer disease. MATERIALS AND METHODS: During the period March 1994 to February 1995, we collected data from 3,652 patients in whom esophagogastroduodenoscopy was done. During this period, when the cancerous or ulcerative lesions in stomach or duodenum were found, rapid urease tests were performed. RESULTS: Six patients had concurrent gastric carcinoma and duodenal ulcer disease. Three of the cases had early gastric carcinoma; 2 had active duodenal ulcers and one had a duodenal ulcer scar; all 3 had positive rapid urease tests. The patients with early gastric cancer were younger than the individuals with advanced gastric cancer. CONCLUSIONS: The co-existence of both diseases may be higher than reported from Western countries or from Peru which may either reflect the high prevalence of circulation of H. pylori ulcer and cancer strains in Korea and the co-infection with both types of organism in some individuals.

Adult↗