• Journal of fish pathology
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• v.20 no.1
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• pp.33-40
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• 2007

Biochemical characteristic of Streptococcus iniae and Streptococcus parauberis that are pathogens of streptococcosis of cultured flounder, Paralichthys olivaceus, in Jeju area was examined. The result of experiments on the grow according to temperatures showed that only S. parauberis grew at 10℃, the result of hemolysis test showed that only S. iniae bacteria showed β hemolysis. Only S. parauberis were positive in VP test and HIP test, both bacteria used α-D-glucose, D-mannose, D-psicose, D-trehalose, pyruvatic acid methyl ester, and glycerol as substrates. L-lactic acid was used only S. iniae bacteria, and β-methyl-D-glucosid was used only by S. parauberis. S. iniae exhibited acute infection patten, differently S. parauberis exhibited chronic infection patten in pathogenic test.

• The Korean Journal of Mycology
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• v.8 no.2
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• pp.89-94
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• 1980

Effects of seed disinfectants on loose smut (Ustilago nuda) and leaf stripe (Pyrenophora graminea) of barley were investigated in field tests. For these experiments, seed samples carrying natural infection of Ustilago nuda and Pyrenophora graminea were used and the following fungicides were used: Baytan, Baytan U, Benlate T, Busan 30, KAC-7703, P 242, Panoctine, Sisthane Ec, Sisthane Wp, Sisthane Ds, Sodium Omadine, Terracoat Zn, Vitathiram and Zinc Omadine, respectively. Results have shown that Sisthane and Benlate T have equal effect to Vitathiram against Ustil­ago nuda and Pyrenophora graminea. Baytan U was effective against loose smut but inferior to leaf stripe of barley. P 242 was effective against leaf stripe but inferior to loose smut of barley. Busan 30 have shown moderately inferior effect to Vitathiram against loose smut and leaf stripe of barley. A mild inhibition of seed germination and seedling growth of barley, naked barley and wheat seeds was observed when high concentration of Sisthane and Baytan U were treated in seedling box placed in green house conditions, but no symptom observed in field conditions.

• The Journal of Korean Society of Virology
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• v.30 no.1
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• pp.83-99
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• 2000

A defective HIV-1 helper virus DNA, pHyPC, was assembled by deleting the RNA packaging signal, env, nef and the 3'LTR sequences. HIV-1 like virus particles that carry the HIV-1 receptor, CD4 were generated by co expression of pHyPC and plasmid DNAs encoding different chimeric CD4 proteins. The CD4 particles, sharing the CD4 ectodomain, precisely fused to different membrane anchors. CD4(+) particles specifically bound to HIV-1 Env expressing cells, but any signs of infection into these cells were not detected. Binding was only partially blocked by either polyclonal anti-CD4 antibodies or by high concentrations of soluble CD4. Surprisingly, CD4(+) particles also adsorbed to HeLa, CHO, NIH3T3 and COS-7 cells in the absence of HIV-1 Env expression. Adsorption was comparable in strength and speed to the highly specific CD4-Env interaction. CD4(-) particles exhibited only background levels of binding. Cell binding was CD4. dependent, but it was independent of the cell type from which the CD4(+) particles originated. Interestingly, CD4-dependent/Env-independent binding was only found when CD4 was present on virus particles. This suggests that the micro-environment of CD4 on virus particles uniquely expose this new cell binding activity. Its high affinity could explain in part why infection of Env(+) cells by CD4(+) particles was not detected. Further experiments will be required to evaluate whether this strong membrane interaction could represent one step in the multiple-step viral entry process.

• The Plant Pathology Journal
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• v.29 no.1
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• pp.17-30
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• 2013

Barley stripe mosaic virus (BSMV) induces massive actin filament thickening at the infection front of infected Nicotiana benthamiana leaves. To determine the mechanisms leading to actin remodeling, fluorescent protein fusions of the BSMV triple gene block (TGB) proteins were coexpressed in cells with the actin marker DsRed: Talin. TGB ectopic expression experiments revealed that TGB3 is a major elicitor of filament thickening, that TGB2 resulted in formation of intermediate DsRed:Talin filaments, and that TGB1 alone had no obvious effects on actin filament structure. Latrunculin B (LatB) treat-ments retarded BSMV cell-to-cell movement, disrupted actin filament organization, and dramatically decreased the proportion of paired TGB3 foci appearing at the cell wall (CW). BSMV infection of transgenic plants tagged with GFP-KDEL exhibited membrane proliferation and vesicle formation that were especially evident around the nucleus. Similar membrane proliferation occurred in plants expressing TGB2 and/or TGB3, and DsRed: Talin fluorescence in these plants colocalized with the ER vesicles. TGB3 also associated with the Golgi apparatus and overlapped with cortical vesicles appearing at the cell periphery. Brefeldin A treatments disrupted Golgi and also altered vesicles at the CW, but failed to interfere with TGB CW localization. Our results indicate that actin cytoskeleton interactions are important in BSMV cell-to-cell movement and for CW localization of TGB3.

• Korean Journal of Veterinary Research
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• v.15 no.2
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• pp.279-285
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• 1975

The experiments were conducted to isolate the etiogical agent and to survey the distribution of Nosema disease in honey bees. The results obtained were as follows: 1. The etiological agent of the so-called "crawling disease" in honey bees characterized by the symptoms of crawling, diarrhea, and enteritis etc. was first isolated and identified with Nosema apis (Zander 1909) in Korea. 2. 455 colonies were randomely sampled and surveyed in 4,766 bee colonies out of 56 apiaries and 51 colonies (11.2%) out of 455 bee colonies were infected with N, apis. 3. Infection rates according to the period of honeyflow as follows: Brassica napus (Apr.): 25/130 colonies (18.4%) Rohinia pseudoacacia (May) : 8/55 colonies (14.%) Trifolium repels(Jun.): 15/99 colonies (13.6%) Castanea crenate (Jul.): 3/46 colonies (6.5%) Lespedeza bicolor(Aug.): 0/60 colonies (-) Fagopyrumesculentum(Sept.) & Perilla frutescens(Oct.) 0/65 colonies (-) 4. The typical clinical signs of Nosema disease were appeared on loth day after N. apis was orally administered with the level of $16{\times}10^4$ spores/ml to the healthy adult bees. Spores could be harvested with the level of $121{\sim}236{\times}10^4$ spores/ml on 10th day and $392{\sim}429{\times}10^4$ spores/ml on 15 days after infection. 5. In adult honey bees infected with N. apis artificially the 50% lethal day of life-span was 9 to 10 days and 100% lethal day was 16 to 19 days. However, in the control 50% lethal day was 19 to 23 days and 100% lethal day was 31 to 33 days.

• YAKHAK HOEJI
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• v.55 no.3
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• pp.227-233
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• 2011

We previously reported the protein isolated from Coptidis Rhizoma (CRP), which has antifungal activity against a fungal pathogen, Candida albicans. In the current study, we investigated what portion in the CRP is responsible for the antifungal activity. For the investigation, the CRP was fractionated on a Shepadex G-50 column. Data resulting from the fractionation, seven fractions were obtained. Fractions (Fr.) I, II, and III eluted initially from the column showed no inhibitory effect on the growth of C. albicans, whereas Fr. IV, V, and VI eluted later revealed inhibition of the growth, and Fr. IV and VI showed potent antifungal activity by broth susceptibility analysis. However, Fr. VI was contained in the CRP more than Fr. IV, which led us to select the VI for the following experiments. In a murine model of a subcutaneous candidiasis caused by C. albicans, the Fr. VI displayed a therapeutic effect on nude mice pretreated with anti-neutrophil monoclonal antibody (RB68C5) and then infected subcutaneously with live C. albicans. At day 16, these mice were healed almost up to 78% of the infected area when compared to infected area of control nude mice that received diluent (Dulbecco's Phosphate-Buffered Saline; DPBS), instead of the Fr. VI (P<0.01). The Fr. VI blocked hyphal formation from blastoconidial form of C. albicans (P<0.01), which might prevent penetration of hyphae to the deeper site of skin and thus helps the healing. In the ionic strength test, the effect of Fr. was influenced by $Ca^{2+}$ ion just like other known antimicrobial peptides, but the influence was affected at an extremely high concentration such as 500 mM. Thus, such ion-concentration is considered to be meaningless in the clinical situation. Considering all data together, Coptidis Rhizoma is appeared to produce an antimicrobial peptide that has therapeutic effect on subcutaneous infection caused by C. albicans.

• International Journal of Oral Biology
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• v.43 no.3
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• pp.141-146
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• 2018

Periodontitis is generally a chronic disorder characterized by breakdown of tooth-supporting tissues, producing dentition loss. Porphyromonas gingivalis (P. gingivalis), a Gramnegative anaerobic rod, is one of the major pathogens associated with periodontitis. Neutrophils are first line defense cells in the oral cavity that play a significant role in inflammatory response. Xylitol is a known anti-caries agent and has anti-inflammatory effects. In this study, we conducted experiments to evaluate anti-inflammatory effects of xylitol on P. gingivalis infected neutrophils for possible usage in prevention and treatment of periodontal infections. P. gingivalis was intraperitoneally injected and peritoneal lavage was collected for cytokine determination. For in vitro study, neutrophils were collected from mouse peritoneal cells after zymosan injection or bone marrow cells. Neutrophils were stimulated with live P. gingivalis and ELISA was used to determine the effect of xylitol on P. gingivalis induced cytokine production. $IL-1{\beta}$, IL-6, $TNF-{\alpha}$ concentration and neutrophil population in the peritoneal lavage was increased in P. gingivalis-infected mouse. Peritoneal cells infected with live P. gingivalis revealed significantly increased production of $IL-1{\beta}$, IL-6 and $TNF-{\alpha}$ at multiplicity of infection of 10. Neutrophils from bone marrow and peritoneal lavage revealed increased production of $IL-1{\beta}$, IL-6 and $TNF-{\alpha}$. Xylitol significantly mitigated P. gingivalis induced cytokine production in neutrophils. Findings indicate that xylitol is an anti-inflammatory agent in neutrophils infected with live P. gingivalis, that suggests its use in periodontitis management.

• International Journal of Oral Biology
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• v.42 no.1
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• pp.33-38
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• 2017

Background: Periodontitis is an inflammatory disease characterized by the breakdown of tooth-supporting tissues, leading to tooth loss. Aggregatibacter actinomycetemcomitans are major etiologic bacterium causing aggressive periodontitis. Ursodeoxycholic acid (UDCA), a hydrophilic gall bladder acid, has been used as an effective drug for various diseases related to immunity. The aim of this study was to investigate the effect of UDCA on the inflammatory response induced by A. actinomycetemcomitans. Methods: A human acute monocytic leukemia cell line (THP-1) was differentiated to macrophage- like cells by treatment with phorbol 12-mystristate 13-acetate (PMA) and used for all experiments. The cytotoxic effect of UDCA was examined by MTT assay. THP-1 cells were pretreated with UDCA for 30 min before A. actinomycetemcomitans infection and the culture supernatant was analyzed for various cytokine production by ELISA. The effect of UDCA on bacterial growth was examined by measuring optical densities using a spectrophotometer. Results: UDCA showed no cytotoxic effect on THP-1 cells, up to $80{\mu}M$ Ed highlight: Please confirm technical meaning. UDCA pretreatment inhibited the A. actinomycetemcomitans-induced $IL-1{\beta}$, $TNF-{\alpha}$, and IL-17A secretion in a dose-dependent manner. UDCA also inhibited IL-21 production at $60{\mu}M$. The production of IL-12 and IL-4 was not influenced by A. actinomycetemcomitans infection. Conclusion: These findings indicate that UDCA inhibits the production of inflammatory cytokines involved in innate and Th17 immune responses in A. actinomycetemcomitans-infected THP-1- derived macrophages, which suggests its possible use for the control of aggressive periodontitis.

• Korean Journal of Animal Reproduction
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• v.16 no.2
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• pp.175-184
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• 1992

These experiments were investigate the effects of bacterial infection of uterus and vagina during bovine embryo transferring on the development of embryo. We examined the distribution of reproductive disordered cow by akind of disease, identified the bacteria isolated from the vagina of those cows and bacterial infectin of media and its treatment with several kinds of antibiotics at that. The results obtained were summarized as follows ; 1. The total 592 reproductive disordered cows were caused by ovarian dysfunction(43.4%), ovary-uterus complication(24.5%), endometrities(17.7%), and repeat breeder(12.0%). 2. The main bacteria among 11 kinds of bacteria(113 colonies) was E. coli(38 colonies, 33.6%). Likewise, E. coli was propotioned to 23 and 22.7% among bacteria from vagina of endometritis and repeat breeder, respectively. 3. The sensitivities of viginal bacteria to pencillin and streptomycin were 6.2 and 4.4% respectively, but those to gentamycin and chloramphenicol were 22.1 and 16.8%, respectively. The similar sensitivities were found in the embryo recovery media. 4. The rates of bacterial infection of recovery medim and that of abnormal development of embryo were 75 and 80%, respectively. 5. The antibiotic sensitivity assay of ova recovery media showed gentamicin and chloramphenicol gave better results than streptomycin and penicillin. 6. The developmental rate of 1-cell stage mice embryos was 34.0% in bacterial infected culture media, but was 40.0, 58.0, 40.0 or 30.0% with the treatment of kanamycin, gentamycin, chloramphenicol, streptomycin, or penicillin, respectively.

• Clinics in Orthopedic Surgery
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• v.10 no.4
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• pp.427-432
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• 2018

Background: The purpose of this study was to evaluate the usefulness of sonication technique for microbiological diagnosis and the sterility of the recycled autoclaved femoral components from infected total knee arthroplasty (TKA) using a sonication method. Methods: Nineteen femoral implants explanted from patients with infected TKA were sterilized with a standard autoclave method. Standard culture of the fluid before and after sonication of the sterilized implants was performed to detect pathogenic microorganisms. Additional experiments were performed to evaluate the sterility of the recycled implant by inducing artificial biofilm formation. Methicillin-resistant Staphylococcus aureus (MRSA) was inoculated into 10 implants and sterilization in a standard autoclave was performed, and then the fluid was cultured before and after sonication. Results: Two of the 19 sterilized implants were positive for growth of bacteria after sonication, whereas no growth was detected in the cultured fluid from the sterilized implants before sonication. The bacteria were Staphylococcus species in all two cases. In one of 10 implants inoculated with MRSA, the culture was positive for growth of bacteria both before and after sonication. However, Staphylococcus epidermidis was cultured from both occasions and thus this implant was thought to be contaminated. Conclusions: We found sonication for identification of pathogens could be helpful, but this finding should be interpreted carefully because of the possibility of contamination. Sterilization of an infected femoral implant with an autoclave method could be a good method for using the temporary articulating antibiotic spacer in two-stage revision arthroplasty.