• 대한수의학회지
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• 제58권2호
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• pp.95-98
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• 2018

Brucellosis is one of the common zoonoses caused by Brucella abortus (B. abortus). However, little has been reported on factors affecting invasion of B. abortus into host cells. To investigate cell-type dependent invasion of B. abortus, phagocytic RAW 264.7 and THP-1 cells and non-phagocytic HeLa cells were infected with wild-type and mutant B. abortus, and their invasion efficiencies were compared. The invasion efficiencies of the strains were cell-type dependent. Wild-type B. abortus invasion efficiency was greater in phagocytic cells than in epithelial cells. The results also indicated that there are different factors involved in the invasion of B. abortus into phagocytic cells.

• Journal of Microbiology and Biotechnology
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• 제15권6호
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• pp.1368-1376
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• 2005

Pseudomonas aeruginosa produces a variety of bacteriocidal substances including pyocins that are active against the same species, but their physiological roles are relatively unknown. Here, we profiled the bacteriocidal activities in the culture supernatants of various P. aeruginosa isolates and describe the competitive growth advantages of strains PAO1 and PA14 over some strains including PAK, which are sensitive to their bacteriocidal activities. These findings suggest that the factors governing the production of pyocins and the resistance to them play important roles in controlling P. aeruginosa populations in its local environments.

• 대한예방의학회:학술대회논문집
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• 대한예방의학회 1999년도 제51차 추계 학술대회 연제집
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• pp.64-65
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• 1999

• Journal of Microbiology and Biotechnology
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• 제24권6호
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• pp.854-861
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• 2014

The diagnosis of Brucella abortus is mainly based on serological methods using antibody against LPS, which has diagnostic problems. Therefore, to solve this problem, we evaluated two proteins of B. abortus, Cu/Zn superoxide dismutase (SodC) and outer membrane proteins 2b porin (Omp2b). The genes were cloned and expressed in a pMAL system, and the recombinant proteins, rOmp2b and rSodC, were purified as fusion forms with maltose-binding protein. The identity of the proteins was confirmed by SDS-PAGE and Western blot analysis with sera of mice infected with B. abortus. Production of cytokines and nitric oxide (NO) was investigated in RAW 264.7 cells and mouse splenocytes after stimulation with the proteins. Moreover, cellular and humoral immune responses were investigated in BALB/c mice after immunization with the proteins. TNF-${\alpha}$, IL-6, and NO were significantly inducible in RAW 264.7 cells. Splenocytes of naive mice produced IFN-${\gamma}$ and IL-4 significantly by stimulation. Moreover, number of IgG, IFN-${\gamma}$, and IL-4 producing cells were increased in immunized mice with the two proteins. Production of IgG and IgM with rOmp2b was higher than those with rSodC in immunized mice. These results suggest that the two recombinant proteins of B. abortus may be potential LPS-free proteins for diagnosis.

• IMMUNE NETWORK
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• 제23권6호
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• pp.43.1-43.10
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• 2023

The continuous emergence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) variants has provided insights for updating current coronavirus disease 2019 (COVID-19) vaccines. We examined the neutralizing activity of Abs induced by a BA.4/5-containing bivalent mRNA vaccine against Omicron subvariants BN.1 and XBB.1.5. We recruited 40 individuals who had received a monovalent COVID-19 booster dose after a primary series of COVID-19 vaccinations and will be vaccinated with a BA.4/5-containing bivalent vaccine. Sera were collected before vaccination, one month after, and three months after a bivalent booster. Neutralizing Ab (nAb) titers were measured against ancestral SARS-CoV-2 and Omicron subvariants BA.5, BN.1, and XBB.1.5. BA.4/5-containing bivalent vaccination significantly boosted nAb levels against both ancestral SARS-CoV-2 and Omicron subvariants. Participants with a history of SARS-CoV-2 infection had higher nAb titers against all examined strains than the infection-naïve group. NAb titers against BN.1 and XBB.1.5 were lower than those against the ancestral SARS-CoV-2 and BA.5 strains. These results suggest that COVID-19 vaccinations specifically targeting emerging Omicron subvariants, such as XBB.1.5, may be required to ensure better protection against SARS-CoV-2 infection, especially in high-risk groups.

• 한국입자에어로졸학회지
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• 제6권2호
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• pp.81-90
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• 2010

Several studies have suggested the possibility of airborne transmission of infectious diseases such as tuberculosis, pandemic influenza. because the number of patients increases explosively, if infectious disease had a high basic reproduction number, pharmaceutical interventions such as vaccination, chemoprophylaxis in the early stage of epidemic. Thus, non-pharmaceutical interventions such as mask-wearing, installing air cleaners, school closure are important to control and prevent the infectious diseases. However, the current technology on the mask, air cleaning, ventilation, and etc., seems to be not originated from the understanding of infection via airborne transmission. It is important to estimate the aerodynamic behavior of saliva droplets by coughing or speaking in order to understand the phenomena of airborne infection. In addition, the prediction of transmission of infectious diseases through the air is critical to prevent or minimize the damage of infection. In this review, we reviewed the recent studies on the airborne infection by focusing on the aerodynamic characteristics of saliva droplets and modeling of airborne transmission.

• Nuclear Medicine and Molecular Imaging
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• 제40권4호
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• pp.193-199
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• 2006

Infectious and inflammatory bone diseases include a wide range of disease process, depending on the patient's age, location of infection, various causative organisms, duration from symtom onset, accompanied fracture or prior surgery, prosthesis insertion, and underlying systemic disease such as diabetes, etc. Bone infection may induce massive destruction of bones and joints, results in functional reduction and disability. The key to successful management is early diagnosis and proper treatment. Various radionuclide imaging methods including three phase bone scan, Ga-67 scan, WBC scan, and combined imaging techniques such as bone/Ga-67 scan, WBC/bone marrow scan add complementary role to the radiologic imaging modalities including plain radiography, CT and MRI. F-18 FDG PET imaging also has recently been introduced in diagnosis of infected prosthesis and chronic active osteomyelitis. Selection of proper nuclear medicine imaging method will improve the diagnostic accuracy of infections and inflammatory bone diseases, based on understading of pathogenesis and radiologic imaging findings.

• IMMUNE NETWORK
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• 제23권4호
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• pp.33.1-33.13
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• 2023

Vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been acknowledged as an effective mean of preventing infection and hospitalization. However, the emergence of highly transmissible SARS-CoV-2 variants of concern (VOCs) has led to substantial increase in infections among children and adolescents. Vaccine-induced immunity and longevity have not been well defined in this population. Therefore, we aimed to analyze humoral and cellular immune responses against ancestral and SARS-CoV-2 variants after two shots of the BNT162b2 vaccine in healthy adolescents. Although vaccination induced a robust increase of spike-specific binding Abs and neutralizing Abs against the ancestral and SARS-CoV-2 variants, the neutralizing activity against the Omicron variant was significantly low. On the contrary, vaccine-induced memory CD4⁺ T cells exhibited substantial responses against both ancestral and Omicron spike proteins. Notably, CD4⁺ T cell responses against both ancestral and Omicron strains were preserved at 3 months after two shots of the BNT162b2 vaccine without waning. Polyfunctionality of vaccine-induced memory T cells was also preserved in response to Omicron spike protein. The present findings characterize the protective immunity of vaccination for adolescents in the era of continuous emergence of variants/subvariants.

• Clinical and Experimental Pediatrics
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• 제54권12호
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• pp.489-500
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• 2011

Compared to the past decades, in recent decades, environmental and hygienic conditions in the Republic of Korea have improved along with socioeconomic developments, and the incidence of most infectious diseases, especially vaccine-preventable diseases, has greatly decreased due to active immunization with the developed level of health care. However, the incidence of some diseases has been increasing, and new diseases have been emerging. To cope with such changes actively, the government put the "Law for Control and Prevention of Infectious Diseases" into effect; this law was entirely revised on December 30, 2010. In this report, I review the past and recent status of infectious diseases in the Republic of Korea, following the introduction of this law, on the basis of data in the "National Notifiable Disease Surveillance System", which had been accumulated between the years 1960 and 2010.

• 대한수의학회지
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• 제52권1호
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• pp.33-38
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• 2012

Germanium biotite, a natural mineral, has been used as a feed supplement to reinforce innate immune ability. The aim of the present study was to evaluate the effects of germanium biotite on the adsorptive and inhibition of growth abilities against Escherichia (E.) coli and Salmonella spp. in vitro. Two strains of enterotoxigenic E. coli and four strains of two Salmonella serotypes (Salmonella Derby and Salmonella Typhimurium), major bacterial diarrheal pathogens, were used for this experiment. The absorptive ability of germanium biotite against most Salmonella used in present experiment was observed weakly. The germanium biotite, however, showed significant effect of bacterial growth inhibition in most experiment bacteria. These results suggest that the use of the germanium biotite as feed supplement could alleviate diarrhea following inhibition of bacteria growth. It is also presumed that antibiotics usage for farm animals, considered as causes of antibiotic residue in meat and emerging antibiotic resistance, could be reduced through the use of germanium biotite as a feed supplement, in place of antibiotics used for the prevention of diarrhea.