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Biomedical subjects

K Oh

Publications and source records attributed to K Oh.

At least 19 recordsLinked to original sources
PubMed2003

Broadband amplified spontaneous emission from an Er(3+)-Tm(3+)-codoped silica fiber.

A new type of amplified spontaneous emission (ASE) based on an Er-Tm-codoped silica fiber is reported. When the fiber was pumped at 980 nm, the emission yielded a 3-dB bandwidth over 90 nm (1460-1550 nm) without any external filters, which is twice larger than that produced by conventional Er-doped fiber ASE sources. We believe that the superposition of two ASE bands, one from Er ions near 1530 nm and the other from Tm ions near 1450 nm, results in the broad bandwidth. Temperature-dependent ASE powers and fiber-length-dependent spectra strongly suggest that photon-assisted energy transfer between the sensitizing ion, Er, and the acceptor ion, Tm, plays an important role in changes in the bandwidth's size.

Journal Article↗
PubMed2001

Multiple pathways governing Cdx1 expression during murine development.

Cdx1 encodes a mammalian homeobox gene involved in vertebral patterning. Retinoic acid (RA) is likewise implicated in vertebral patterning. We have previously shown that Cdx1 is a direct retinoid target gene, suggesting that Cdx1 may convey some of the effects of retinoid signaling. However, RA appears to be essential for only early stages of Cdx1 expression, and therefore other factors must be involved in maintaining later stages of expression. Based on function and pattern of expression, Wnt family members, in particular Wnt3a, are candidates for regulation of expression of Cdx1. Consistent with this, we confirm prior results which demonstrated that Cdx1 can be directly regulated by Wnt signaling, and identify functional LEF/TCF response motifs essential for this response. We also find that Cdx1 expression is markedly attenuated in a stage- and tissue-specific fashion in the Wnt3a hypomorph vestigial tail, and present data demonstrating that Wnt3a and RA synergize strongly to activate Cdx1. Finally, we show that Cdx1 positively regulates its own expression. These data prompt a model whereby retinoid and Wnt signaling function directly and synergistically to initiate Cdx1 expression in the caudal embryo. Expression is then maintained, at least in part, by an autoregulatory mechanism at later stages.

Animals↗
PubMed2001

Idiopathic juxtafoveal retinal telangiectasis: case report and literature review.

BACKGROUND: Idiopathic juxtafoveal retinal telangiectasis (IJRT) is an uncommon cause of vision loss. It is characterized by irregularly dilated capillaries in the macula, often found temporal to the fovea and straddling the horizontal raphe. These telangiectatic vessels appear similar to microaneurysms and can be difficult to detect without fluorescein angiography. Varying degrees of vessel leakage and exudation are also common features. Three distinct types of IJRT have been described on the basis of clinical features. Within the spectrum of disease encompassed by IJRT, it can affect either gender--present unilaterally or bilaterally--and occur at any age. CASE REPORT AND REVIEW: Presented here is a case with type 1A idiopathic juxtafoveal retinal telangiectasis and a review of all types.

Diagnosis, Differential↗
PubMed1999

Douching: a problem for adolescent girls and young women.

OBJECTIVE: To compile available published data on the prevalence of douching practices in adolescent girls and young women and the effects of douching on gynecologic health, including studies of gynecologic changes due to douching in adolescent girls and young women, surveys that demonstrated the prevalence of douching in the populations, and policy statements or lack thereof from professional and medical organizations with regard to the practice of douching. DATA SOURCES: We did Internet searches, including a MEDLINE search, a literature review, and used the telephone, mail, and e-mail to contact professional organizations. RESULTS: Douching has been found to be strongly associated with increased risk for pelvic inflammatory disease, bacterial vaginosis, and ectopic pregnancy, the former of which is especially prevalent in adolescent girls and young women. Douching is practiced by 15.5% of adolescent girls and young women in the United States, with significantly higher prevalences in certain groups in the population. We have not found any official position of professional and medical organizations on the practice of douching. CONCLUSIONS: Because vaginal douching has been shown to be associated with bacterial vaginosis, pelvic inflammatory disease, and ectopic pregnancy, and because no benefits are conferred on those who practice it, douching should be discouraged among adolescent girls and young women. There is a great need for further studies, particularly prospective ones, to determine if there is evidence of a direct causative influence of douching on pelvic inflammatory disease, ectopic pregnancy, and/or bacterial vaginosis, and to determine why adolescent girls and young women douche.

Female↗
PubMed1998

Correlation between endoscopic severity and the clinical activity index in ulcerative colitis.

OBJECTIVE: The aim of this study was to examine the relationship between a new activity index and the endoscopic severity assessed by sigmoidoscopy in patients with ulcerative colitis. METHODS: We evaluated the sigmoidoscopic severity and Activity Index (AI) in 37 patients with distal colitis, 23 with left-sided colitis, and 36 with total colitis, in which the severity was divided into three categories: grade 1 = mildly active, grade 2 = moderately active, and grade 3 = severely active. We examined the relationship between the AI or clinical parameters and the endoscopic severity in all 96 cases. RESULTS: The AI was found to be significantly correlated with the degree of sigmoidoscopic activity in all cases, as well as in those with distal colitis, left-sided colitis, or total colitis. When patients with both grade 1 sigmoidoscopic activity and AI values of less than 150 were regarded to have mild colitis and patients with either grade 2 or grade 3 sigmoidoscopic activity and AI values of more than 150 were regarded to have moderate or severe colitis, 10 of 37 (27%) in the distal colitis, one of 23 (4.3%) in the left-sided colitis, and four of 36 (11.1%) in the total colitis groups were thus misclassified regarding the distinction between mild colitis and moderate or severe colitis. Three of four patients with severity of grade 1, indicating AI values of more than 150, had total colitis, whereas the remaining one had left-sided colitis. On the other hand, 10 of 11 patients with severity of grades 2 or 3 with AI values of less than 150 had distal colonic involvement. When the endoscopic activity was equivalent, the highest mean AI values occurred in total colitis whereas the lowest mean AI values were found in distal colitis. CONCLUSIONS: The AI well reflects the sigmoidoscopic activity. High AI values with a low sigmoidoscopic severity are thus considered to reflect extensive involvement, whereas a high sigmoidoscopic severity with low AI values is thought to indicate the involvement of the distal colon.

Adolescent↗
PubMed1997

Case report: eosinophilic colitis with high antibody titre against Ascaris suum.

Eosinophilic gastroenteritis (EGE) is an inflammatory disease characterized by eosinophilic infiltration of the gastrointestinal tract accompanied by varying abdominal symptoms and usually by peripheral blood eosinophilia. Although the precise aetiology of EGE remains to be determined, contribution of allergic process to certain allergens, such as foods, drugs and parasites, has been repeatedly proposed as the pathogenesis of the disease. Here we report on a rare case of a woman who had extensive eosinophilic infiltration in the descending and rectal colon with a high titre of IgG antibody against Ascaris suum. The patient was successfully treated with prednisolone.

Animals↗
PubMed1996

An in vitro assay for detection of glomerular binding IgG autoantibodies in patients with systemic lupus erythematosus.

The deposition of anti-dsDNA antibodies in the glomerulus is believed to play a critical role in the pathogenesis of nephritis in SLE. However, an absolute correlation between serum levels of anti-dsDNA antibodies and renal disease has not been found. Recently a glomerular binding assay (GBA) has been developed to detect IgG binding to isolated rat glomeruli. We have used the GBA to study sera from four groups of SLE patients: (A) + anti-dsDNA antibodies, active nephritis; (B) - anti-dsDNA antibodies, active nephritis; (C) + anti-dsDNA antibodies, no nephritis; and (D) - anti-dsDNA antibodies, no nephritis. The serum anti-dsDNA antibodies in group A and group C patients could not be distinguished on the basis of isotype, charge, or cross-reactivity with histones. Nevertheless, the mean intensity of glomerular immunofluorescence was significantly higher in group A than in the three other patient groups and distinguished between patients with serum anti-dsDNA antibodies who had nephritis and those without clinically apparent nephritis. GBA reactivity was unaffected by DNase treatment of sera, but was partially inhibited by preincubation with dsDNA. These findings are consistent with the hypothesis that some anti-dsDNA antibodies cross-react with glomerular components and that the presence of this cross-reactivity is associated with, and may be responsible for, the development of nephritis. In addition, we have identified a group of SLE patients with renal disease and typical renal histopathology and immune deposits who do not have serum anti-dsDNA antibodies or antibodies that directly bind to glomeruli in the GBA. The mechanism of renal immune deposition in these patients remains to be determined.

Autoantibodies↗
PubMed1996

Effect of the eradication of Helicobacter pylori on duodenal ulcer healing and ulcer relapse: randomized controlled study in Japan.

To investigate the effect of the eradication of Helicobacter pylori on the healing and relapse of duodenal ulcers. 50 patients with active duodenal ulcer and H. pylori infection were randomly allocated to two treatment groups. One group (cimetidine group) received cimetidine 400 mg twice daily for 6 weeks and the other group (double-therapy group) received 300 mg amoxicillin granules and 250 mg metronidazole thrice daily for 2 weeks, in addition to the same regimen of cimetidine as the cimetidine group. Forty-two patients completed the study. After confirmation of ulcer scar, all patients were followed up for 6 months while receiving treatment with teprenone, an agent that does not affect acid secretion or the eradication of H. pylori. The healing rates at 6 weeks were 90% in the cimetidine group and 95.5% in the double-therapy group. H. pylori eradication occurred in 0% of the cimetidine group and in 73.7% of the double-therapy group (P = 0.004). The cumulative relapse rates in the two groups at 6 months were 64.3% and 11.1%, respectively (P = 0.0007). In the double-therapy group, the cumulative relapse rate at 6 months in the patients in whom H. pylori persisted was 50% (2/4); the rate was 0% (0/14) in the patients in whom H. pylori had been eradicated (P = 0.005). Histological gastritis significantly improved compared with the baseline in the double-therapy group, but no such improvement was seen in the cimetidine group. White scarring was found in 7.1% of the cimetidine group and in 83.3% of the double-therapy group after 6 months (P < 0.0001). The eradication of H. pylori markedly decreased the relapse rate in duodenal ulcer patients, and it significantly improved both the grade of gastritis and the quality of the ulcer scar.

Adult↗
PubMed1995

Evaluation of disease activity in patients with moderately active ulcerative colitis: comparisons between a new activity index and Truelove and Witts' classification.

OBJECTIVES: We have recently proposed a new activity index (AI) for ulcerative colitis. The aim of this study was to examine how AI would reflect the effect of medical therapy in comparison with Truelove and Witts' criteria. METHODS: In this trial, we studied 35 patients with extensive colitis who persisted with moderate disease for 2 wk. They showed no change in disease activity according to Truelove and Witts' classification despite 2 wk of corticosteroid therapy. Nine of the 35 patients underwent surgery (operated group), and 26 responded to the medical therapy and went into remission (nonoperated group). RESULTS: In the nonoperated group, AI values significantly decreased at 1 and 2 wk after treatment compared with pretreatment values, whereas there was no significant change in AI in the operated group during the clinical course. Remission occurred in all patients indicating below 180 of AI values 2 wk after therapy, whereas approximately 65% of patients indicating above 180 of AI values subsequently needed colectomy. CONCLUSIONS: This study suggests that AI will be useful in evaluation of response to medical therapy and prediction of remission and colectomy in patients with moderately active ulcerative colitis.

Adult↗
PubMed1994

[Basic and clinical studies on biapenem (L-627) in obstetrics and gynecology].

UNLABELLED: We investigated biapenem (BIPM, L-627) a newly carbapenem antibiotic, for its antibacterial activity, tissue penetration, clinical efficacy and bacteriological effect in obstetric and gynecological infections, and obtained the following results. 1. Antibacterial activity: MICs of L-627 against 149 strains isolated from 80 patients in this clinical trial were examined and compared with those of imipenem (IPM) and ceftazidime (CAZ). The MIC50 and MIC90 of L-627 against the isolates were 0.2 and 12.5 micrograms/ml, respectively. Those of IPM were 0.2 and 6.25 micrograms/ml, respectively. The antibacterial activity of L-627 was quite similar to that of IPM, and was superior to that of CAZ. 2. Tissue and retroperitoneal fluid penetration: The peak levels in venous and uterine arterial sera were 24.0 and 26.2 micrograms/ml, respectively, after 300 mg drip infusion. The peak levels in the uterine or adnexal tissues were 2.39-9.60 micrograms/g, and 0.2 microgram/g of L-627 was detected at 275 minutes after administration. Peak levels in retroperitoneal fluid were 8.7 +/- 1.7 micrograms/ml at 1 hour after the completion of 30 minutes drip infusion (300 mg) and 7.9 +/- 0.2 micrograms/ml at 30 minutes after 300 mg 60 minutes drip infusion (300 mg). These levels expected the MICs against main pathogenic organisms. 3. CLINICAL RESULTS: L-627 was given to the following 144 patients (No. of analytical subjects) at a daily dose of 0.3-1.2 g for 2-13 days: intrauterine infections (54), adnexitis (36), parametritis (17), pelvic peritonitis (27), bartholins abscess (6) and other infections (4). The clinical efficacy was 93.1% (134/144) and the eradication rate against isolated organisms was 88.7% (110/124). Side effects were observed in 2 patients: eruption (1) and vomiting with numbness of the tongue (1). Abnormal change in laboratory test results included increase in eosinophils in 1, increase in GOT, GPT and gamma-GTP in 1 and increase in GPT and A1-P in 1, but all of these abnormalities were very mild and withdrawal of the drug was not required. Our results suggest that this drug is useful in the treatment of gynecological infections.

Adolescent↗
PubMed1994

Musculoskeletal injuries in the fire service: views from a focus group study.

1. The focus group is a qualitative data collection method involving carefully planned small group discussions designed to obtain perceptions on a defined area of interest. Focus groups can be used by occupational health nurses for gathering ecologically based, in-depth needs assessment information from workers prior to program planning. 2. Occupational health nurses can be guided in their needs assessments by an ecological framework that considers the person, workplace, and situational factors that contribute to occupational health problems. 3. A focus group study of fire chiefs and firefighters used an ecological framework to elicit participants' perceptions of the factors that contribute to musculoskeletal injury and the preventive strategies that would be acceptable to them. Participants shared their insights, motivations, and feelings about the factors, thus suggesting concepts and hypotheses to be explored further. 4. The occupational health nurse needs to consider the differing meanings that management and workers attach to an occupational health problem.

Fires↗
PubMed1994

[Obstetrical and gynecological infection].

We discussed the current situation of the intractable bacterial infections in the gyneco-obstetrical field and the countermeasures especially to puerperal fever and pelvic abscess (polymicrobial infection). It is very important to select the proper antibiotics for the treatment, it must be according to the pathobacteriological manifestations of the individual case. We must fix the attention to the infections caused by MRSA.

Abscess↗
PubMed1994

[Establishing a computerized information system: Korean nursing research].

Since 1963 when the graduate program in nursing was initiated in Korea, more than 2,000 students enrolled in the program have published their theses or dissertation papers. However, a few of the study papers have been confined one system, which prohibits them from being used as references by others. This research study provides a database for the nursing thesis and dissertation papers published since 1967 in Korea. This allows for those who are interested in nursing to retrieve the information in effective ways. The retrieval networks as follows: 1) The data is sent via PSTN or DACOM NET to Chonrian by Yonsei Nursing Policy Research Institute. 2) Chonrian saves data. 3) Members of Chonrian retrieve the data through PSTN or DACOM NET.

Databases, Bibliographic↗
PubMed1993

Automatic evaluation of antifungal volatile compounds on the basis of the dynamic growth process of a single hypha.

An automatic analysing system was developed and employed for the evaluation of antifungal activity of volatile compounds in the gas phase. Aspergillus niger was inoculated on agar medium in the reaction vessel. The reaction vessel was incubated at 28 degrees C for 24 h and then a volatile compound was introduced into the vessel either in a batch or flow manner. The antifungal activity of the respective compounds estimated in situ was expressed by the dynamic response parameters of a single hypha. All volatiles tested in the present system inhibited hyphal growth, except linalyl acetate: Limone and geraniol were the most inhibitory. In contrast, linalyl acetate promoted hyphal growth. By definition of the parameters, the fungicidal and fungistatic effects could be distinguished.

Antifungal Agents↗
PubMed1993

Determination of anti-Aspergillus activity of antifungal agents based on the dynamic growth rate of a single hypha.

The dynamic growth rate of a single hypha of Aspergillus niger was analysed using an automatic system. A colony of A. niger was in contact with saline, saline containing an antifungal agent, and flushing saline, in sequence. The growth rate of a test hypha selected arbitrarily from the colony responded dynamically to the antifungal agent. The minimum concentration that caused the complete inhibition of hyphal growth was defined as the minimum inhibitory concentration (MIC). The MIC values obtained were compared with those determined by conventional methods based on increasing rate of colony diameter or dry matter weight.

Amphotericin B↗
PubMed1993

Effects of antimycotics on the biosynthesis of cellular macromolecules in Aspergillus niger protoplasts.

The effects of nine antimycotics on the biosynthesis of cellular macromolecules were analyzed using the regenerating system of protoplasts of Aspergillus niger. The incorporation of several specific radioactive precursors into major cellular components were measured in the presence or in the absence of respective agents. Miconazole, ketoconazole, and tolnaftate inhibited the lipid synthesis. 5-Fluorocytosine strongly inhibited the DNA and protein syntheses. Griseofulvin, however, specifically inhibited the synthesis of cell wall polysaccharides, i.e. chitin and glucan. Other agents showed non-specific inhibition effects. The significance of morphological change of hypha as an indicator of antimycotic action and its feasibility as a screening tool for novel antimycotic compounds are discussed.

Antifungal Agents↗