• The Journal of the Korean Society for Microbiology
• /
• v.35 no.4
• /
• pp.317-324
• /
• 2000

Candida albicans is one of the most frequently isolated fungal pathogens in human. Recently, the prevalence of candida infection has markedly increased, partially due to the increase of immunocompromised hosts. Proposed virulence factors of the pathogenic Candida are the ability to form hyphae to adhere to epithelial cell surfaces, and to secrete acid proteinases and phospholipases. We measured the relative cell surface hydrophobicity (CSH) and the ability of proteinase production (PROT), phospholipase production (PLase), adherence to host epithelium (ADH), and hyphal transition (Germ). The relative risk of virulence factors was analyzed by lethality test in murine model of hematogeneously disseminated candidal infection. According to Cox's proportional hazard analysis, the statistically significant virulence factors were PROT, ADH, and CSH. PROT was the highest risk factor of them. To evaluate the applicability for the diagnosis and treatment of Candidiasis, we examined the protective effect of the active and passive immunizations with the materials purified from virulence factors and antibodies to them in Candia-infected mice model. The mean survival times of active and passive immunized groups were slightly longer than those of non-immunized groups.

• Research in Plant Disease
• /
• v.17 no.3
• /
• pp.302-310
• /
• 2011

Elsinoe fawcettii is one of major pathogenic fungi which cause citrus scab diseases, resulting in fruit blemishes that reduce the economic value of fruit. By increasing interest to safe products of crops, the alternative methods of disease control is highly required. We investigated whether the 215 bacterial strains isolated from Jeju Island possess antifungal effect or suppression effect on the symptom development by Elsinoe fawcettii on citrus. Among them, three bacterial strains THJ 609-3, MRL408-3, and TRH423-3 that exhibited antifungal capacity against Elsinoe fawcettii were selected. To illustrate the disease suppression mechanism, pre-inoculation with the selected bacterial strains was carried out whether could suppress the citrus crab on the leaves. The observation with a fluorescence microscope revealed that the selected bacteria could decrease the number of fungal spores. The ratio of germ tube formation was also decreased by the selected bacterial strains at one day after fungus challenge. The strain THJ 609-3 was identified as Pseudomonas putida as a result of analyzing the internal transcript spaces of the rhizobacterial rDNA. The strains MRL 408-3 and TRH 423-3 were identified as Burkholderia gladioli. Our results may be valuable when the selected rhizobacterial strains used as the environment-friendly microbe for biological control on citrus scab caused by Elsinoe fawcettii.

• The korean journal of orthodontics
• /
• v.33 no.6 s.101
• /
• pp.485-497
• /
• 2003

The form and function of the craniofacial structure critically depend on genetic information. With recent advances in the molecular technology, genes that are important for normal growth and morphogenesis of the craniofacial skeleton are being rapidly uncovered, shaping up modem craniofacial biology. One of them is fibroblast growth factor receptor 2 (FGFR2). Specific point mutations in the. FGFR2 gene have been linked to Apert syndrome, which is characterized by premature closure of cranial sutures and craniofacial anomalies as well as limb deformities. To study pathogenic mechanisms underlying craniosynostosis phenotype of Apert syndrome, we used a transgenic approach; an FGFR2 minigene construct containing an Apert mutation (a point mutation that substitute proline at the position 253 to arginine; P253R) was introduced into fertilized mouse germ cells by DNA microinjection. The injected cells were then allowed to develop into transgenic mice. We used a bone-specific promoter (a DNA fragment from the type I collagen gene) to confine the expression of mutant FGFR2 gene to the bone tissue, and asked whether expression of mutant FGFR2 in bone is sufficient to cause the craniosynostosis phenotype in mice. Initial characterization of these mice shows prematurely closed cranial sutures with facial deformities expected from Apert patients. We also demonstrate that the transgene produces mutant FGFR2 protein with increased functional activities. Having this useful mouse model, we now can ask questions regarding the role of FGFR2 in normal and abnormal development of cranial bones and sutures.

• The Journal of Korean Society for Radiation Therapy
• /
• v.21 no.2
• /
• pp.75-82
• /
• 2009

Purpose: Measure the ozone level in the treatment room while treating a patient so want to know the degree of contamination caused by ozone occurrence. Materials and Methods: Use the linear accelerator (Clinac 21EX, Varian, USA) with the ozone meter (series-200, aeroQual, New Zealand) and water phantom (Wellhofer, IBA, Germany) is irradiated the radiation so that measured the ozone generation level according to MU, dose-rate, SSD, field size, energy, delay time and put the ozone meter in the treatment room actually while treating a patient so measured the daily ozone level variation. Results: While irradiating the radiation, degree of ozone contamination wasn't affected by the energy but mostly in case of electron beam, ozone level was higher than photon beam. The higher dose-rate (0.016~0.025 ppm/hr), the farther SSD (0.018~0.030 ppm/hr), the wider field sizes (0.016~0.025 ppm/hr), the more MU (0.018~0.046 ppm/hr), it occurred high ozone level. Ozone decrement according to delay time changed the background level (0.016 ppm/hr) after elapsed time of 10 minutes from irradiating radiation. And daily ozone occurrence level in the treatment room was below ozone standard level 0.1 ppm/hr (average:0.06 ppm/8 hr) but it could confirm that ozone generation level was included the level (max:0.038 ppm/hr) above 0.02 ppm/hr which patient could perceive. Conclusion: Through ozone level according to variation of certain conditions, actually in the treatment room ozone generation level didn't damaged to patients or workers. Commonly peoples think that ozone was harmful gas but it thought that small amount of ozone generation level while treating a patient was beneficial in the treatment room through air purge action of pathogenic germ or virus sterilization.