• Korean Membrane Journal
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• v.9 no.1
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• pp.52-56
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• 2007

A proton exchange membrane was prepared by ${\gamma}-irradiation-induced$ grafting of styrene into poly(tetrafluoro-ethylene-co-perfluoropropyl vinyl ether) (PFA) and subsequent sulfonation reaction. The degree of grafting (DOG) increased with an increase in the absorbed dose. The prepared membranes showed high ion exchange capacity reaching 3.0 meq/g, which exceeded the performance of commercially available perfluorosulfonic acid membranes such as Nafion. The proton conductivity of PFA-g-PSSA membrane increased with the DOG and reached 0.17 S/cm for the highest sample at room temperature. The DMFC performance of the prepared membranes with 50% DOG was comparable to that of Nafion membrane.

• Journal of Veterinary Clinics
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• v.30 no.1
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• pp.75-79
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• 2013

Laminitis is a common horse disease that causes pain and disability. One of the major causes of laminitis is carbohydrate overload, which leads to the overgrowth of gram-positive bacteria and subsequent toxemia. This study was performed to establish an experimental model of acute phase laminitis. A horse was fed with a bolus dose of oligofructose, examined for clinical signs and blood parameters, and euthanized for necropsy and histopathology. After administration, the horse exhibited clinical signs including watery feces, inappetence, severe lameness, pyrexia and tachycardia. Complete blood count showed increased hematocrit, lymphocytosis and neutropenia. Serum chemistry revealed hyperglycemia, hyperproteinemia, high level of glutamic oxalate transaminase, creatinine, uric acid and mild hyponatremia. Histologically, the lamina tissue was edematous with mild infiltration of inflammatory cells. These findings indicate that oligofructose-induced laminitis in horse is an appropriate model for studying pathogenesis of acute phase laminitis.

• The Korean Journal of Nuclear Medicine
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• v.38 no.3
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• pp.272-273
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• 2004

We experienced a case with meningioma showing false positive I-131 uptake. A 55-years old female patient underwent high dose (150 mCi) radioactive iodine therapy to ablate remnant tissue after total thyroidectomy for papillary thyroid cancer. in addition to intense tracer uptake in thyroid bed, there was mild but focal abnormal uptake in left frontal lobe of the brain on post-therapy I-131 whole body scan. Subsequent brain MR imaging showed single mass lesion in left frontal lobe and the mass was resected under the impression of brain metastasis of thyroid carcinoma. Pathologic report confirmed meningioma from the surgical specimen.

• Tuberculosis and Respiratory Diseases
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• v.80 no.4
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• pp.351-357
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• 2017

In 2011, a cluster of peripartum patients were admitted to the intensive care unit of a tertiary hospital in Seoul with signs and symptoms of severe respiratory distress of unknown etiology. Subsequent epidemiological and animal studies suggested that humidifier disinfectant (HD) might represent the source of this pathology. Epidemiological studies, animal studies, and dose-response analysis demonstrated a strong association between HD use and lung injuries. The diagnostic criteria for HD-associated lung injury (HDALI) was defined on the basis of the clinical, pathological, and radiological attributes of the patients. The clinical spectrum of HDALI appears to range from asymptomatic to full-blown acute respiratory failure, and some patients have required actual lung transplantation for survival. The overall mortality of the exposed population was not significant, although peripartum patients and children who were admitted to the intensive care unit did show high mortality rates. Persistent clinical findings such as diffuse ill-defined centrilobular nodules and restrictive lung dysfunction were observed in some of the survivors. The findings of this review emphasize the importance of assessment of the level of toxicity of chemical inhalants utilized in a home setting, as well as the need to identify and monitor afflicted individuals after inhalational injury.

• The Journal of the Korean dental association
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• v.52 no.4
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• pp.192-202
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• 2014

Bisphosphonate(BP) significantly influence the hone remodeling process. Increasing number of patients with osteoporosis and metastatic bone disease need high dose or long term bisphosphonate therapy. Major adverse effect is jaw bone necrosis and now the bisphosphonate-related necrosis of the jaw(BRONJ) is the major concern of dental practitioner. This study intended to perform the review of the current understandings concerning the pathophysiology of BRONJ. Even though pathophysiological mechanism of BRONJ is not clearly elucidated but now suggested as largely two different concepts; so-called "inside-out" or "outside-in" theory. Inside-out theory emphasize the osteonecrosis of the jaw is the initial major event and subsequent infection and inflammation is the second event that accompanies bone exposure and death of overlying mucosa. However, in "outside-in" theory, infection or inflammation initiated by traumatized oral epithelium is the major event of BRONJ. Both theory would be partially explain BRONJ. Recent research reveals the immune modulating effect and influence of microcrack accumulation by BP. These findings and those of others might explain the missing part of outside-in theory.

• Biomolecules & Therapeutics
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• v.29 no.5
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• pp.519-526
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• 2021

In a search for effective PPAR-γ agonists, 110 clinical drugs were screened via molecular docking, and 9 drugs, including parecoxib, were selected for subsequent biological evaluation. Molecular docking of parecoxib to the ligand-binding domain of PPAR-γ showed high binding affinity and relevant binding conformation compared with the PPAR-γ ligand/antidiabetic drug rosiglitazone. Per the docking result, parecoxib showed the best PPAR-γ transactivation in Ac2F rat liver cells. Further docking simulation and a luciferase assay suggested parecoxib would be a selective (and partial) PPAR-γ agonist. PPAR-γ activation by parecoxib induced adipocyte differentiation in 3T3-L1 murine preadipocytes. Parecoxib promoted adipogenesis in a dose-dependent manner and enhanced the expression of adipogenesis transcription factors PPAR-γ, C/EBPα, and C/EBPβ. These data indicated that parecoxib might be utilized as a partial PPAR-γ agonist for drug repositioning study.

• Korean Journal of Environmental Agriculture
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• v.17 no.1
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• pp.76-83
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• 1998

The most remarkable aspect in the hormesis law is that dose of harmful agents can produce effect that are diametrically opposite to the effect found with high doses of the same agent. Minute quantities of a harmful agent bring about very small change in the organism and control mechanisms appear to subjugate normal processes to place the organism in a state of albert and repair. The stimulated organism in more responsive to changes in environmental factors than it did before being alerted. Routine functions, including repair and defense, have priority for available energy and matetial. The alerted organism utilizes nutrients more efficiently, grows faster, shows improved defense, and lives longer. Accelerated germination, sprouting, growth, development, blooming and ripening, and increased crop yield and resistance to disease are found in plants. Another concept supported by the data in that low doses of ionizing radiation provide increased resistance to subsequent high doses of radiation. The hormesis varies with subject plant, variety, state of seed, environmental and cultural conditions, physiologic function measured, dose rate and total exposure. The results of hormesis are less consistently found, probably due to the great number of uncontrolled variables in the experiments. The general dosage for radiation homlesis in about 100 (10 to 1,000) times ambient or 100 (10 to 1,000) times less than a definitely harmful dose, but these must be modified to the occasion. Although little is known about most mechanisms of homzesis reaction, overcompensation of repair mechanism is offered as one mechanism.

• Korean Journal of Head & Neck Oncology
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• v.21 no.2
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• pp.132-138
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• 2005

Purpose: The purpose of this study was to establish general guidelines for the treatment of patients with early glottic cancer(T1-2N0M0), by assessing the role of primary radiation therapy and by analyzing the tumor-related and treatment-related factors that influence treatment results. We also studied the results of hypofractionated radiation therapy for early glottic cancer. Material and Methods: This retrospective study comprised 48 patients who suffered from early glottic cancer and were treated by primary radiotherapy at Inha University Hospital, between May 1997 and October 2004. T-stage distribution showed 38 patients as T1 and 10 patients as stage T2. Thirty-eight patients underwent hypofractionated radiotherapy using a 6 MY photon beam, a total tumor dose of 63Gy, in 5 weekly fractions of 2.25Gy, with an overall radiation treatment time of 38 days. Ten patients in the T2 stage tolerated a total dose of 63-72 Gy(median 68.4Gy) in 5 weekly fractions of 1.8-2.0Gy, with an overall radiation treatment time of 40-87 days(median 51 days). All patients were followed up for at least 3 years. Univariate and multivariate analyses were performed to identify the prognostic factors affecting the treatment results. Result: The 5-year survival rate was 92% for all patients, 94% for T1 patients and 91% for T2 patients. The local control rate was 93.5% for all patients, 95% for T1 and 92.2% for T2 patients. Three patients suffered a relapse following radiotherapy, and underwent subsequent salvage surgery. We included T-stage, tumor location, total radiation dose, field size and overall radiation treatment time as potential prognostic factors. Only T-stage was found to be statistically significant in the univariate analysis, but in the multivariate analysis, it was not found to be significant. Conclusion: High curative and voice preservation rates were obtained with hypofractionated radiotherapy. Further study with a larger number of patients is needed to determine the prognostic factors affecting treatment results.

• Journal of Microbiology and Biotechnology
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• v.26 no.6
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• pp.1035-1045
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• 2016

To evaluate the effects of lactic acid bacteria (LAB) on Peyer's patch cells, mice were treated with a high dose of kanamycin to disturb the gut microbial environment. The overarching goal was to explore the potential of LAB for use as a dietary probiotic that buffers the negative consequences of antibiotic treatment. In vitro, LAB stimulated the production of immunoglobulin A (IgA) from isolated Peyer's patch cells. Inflammation-related genes (TNF-α, IL-1β, and IL-8) were up-regulated in Caco-2 cells stimulated with lipopolysaccharide (LPS), while tight-junction-related genes (ZO-1 and occludin) were down-regulated; the effects of LPS on inflammatory gene and tight-junction gene expression were reversed by treatment with LAB. Mice treated with a high dose of kanamycin showed increased serum IgE levels and decreases in serum IgA and fecal IgA levels; the number of Peyer's patch cells decreased with kanamycin treatment. However, subsequent LAB treatment was effective in reducing the serum IgE level and recovering the serum IgA and fecal IgA levels, as well as the number of Peyer's patch cells. In addition, ZO-1 and occludin mRNA levels were up-regulated in the ileum tissues of mice receiving LAB treatment. Lactic acid bacteria can enhance the intestinal immune system by improving the integrity of the intestinal barrier and increasing the production of IgA in Peyer's patches. Lactic acid bacteria should be considered a potential probiotic candidate for improving intestinal immunity, particularly in mitigating the negative consequences of antibiotic use.

• Toxicological Research
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• v.21 no.2
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• pp.99-105
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• 2005

Photo-mutagenic compounds have been known to alter skin cancer rates by acting as initiators or by affecting subsequent steps in carcinogenesis. The objectives of this study are to investigate the utility of photo-chromosomal aberration (photo-CA) assay for detecting photo-clastogens, and to evaluate its ability to predict rodent photocarcinogenicity. Photo-CA assay was performed with five test substances that demonstrated positive results in photo-carcinogenicity tests: 8-Methoxypsoralen (photoactive substance that forms DNA adducts in the presence of ultraviolet A irradiation), chlorpromazine (an aliphatic phenothiazine an alpha-adrenergic blocking agent), lomefloxacin (an antibiotic in a class of drugs called fluoroquinolones), anthracene (a tricyclic aromatic hydrocarbon a basic substance for production of anthraquinone, dyes, pigments, insecticides, wood preservatives and coating materials) and Retinoic acid (a retinoid compound closely related to vitamin A). For the best discrimination between the test substance-mediated genotoxicity and the undesirable genotoxicity caused by direct DNA absorption, a UV dose-response of the cells in the absence of the test substances was firstly analyzed. All 5 test substances showed a positive outcome in photo-CA assay, indicating that the photo-CA test is very sensitive to the photo-genotoxic effect of UV irradiation. With this limited data-set, an investigation into the predictive value of this photo-CA test for determining the photo-carcinogenicity showed that photo-CA assay has the high ability of a test to predict carcinogenicity. Therefore, the photo-CA test using mammalian cells seems to be a sensitive method to evaluate the photo-carcinogenic potential of new compounds.