• Journal of Microbiology
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• v.42 no.4
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• pp.278-284
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• 2004

Changes in the soil bacterial community of a coniferous forest were analyzed to assess microbial responses to wildfire. Soil samples were collected from three different depths in lightly and severely burned areas, as well as a nearby unburned control area. Direct bacterial counts ranged from $3.3­22.6\times10^8\;cells/(g{\cdot}soil).$ In surface soil, direct bacterial counts of unburned soil exhibited a great degree of fluctuation. Those in lightly burned soil changed less, but no significant variation was observed in the severely burned soil. The fluctuations of direct bacterial count were less in the middle and deep soil lay­ers. The structure of the bacterial community was analyzed via the fluorescent in situ hybridization method. The number of bacteria detected with the eubacteria-targeted probe out of the direct bacterial count varied from $30.3\;to\;84.7\%,$ and these ratios were generally higher in the burned soils than in the unburned control soils. In the surface unburned soil, the ratios of $\alpha,\;\beta\;and\;gamma-proteobacteria,$ Cytoph­aga-Flavobacterium group, and other eubacteria groups to total eubacteria were 9.9, 10.6, 15.5, 9.0, and $55.0\%,$ respectively, and these ratios were relatively stable. The ratios of $\alpha,\;\beta\;and\;gamma-proteobacteria,$ and Cytophaga-Flavobacterium group to total eubacteria increased immediately after the wildfire, and the other eubacterial proportions decreased in the surface and middle layer soils. By way of contrast, the composition of the 5 groups of eubacteria in the subsurface soil exhibited no significant fluctuations dur­ing the entire period. The total bacterial population and bacterial community structure disturbed by wildfire soon began to recover, and original levels seemed to be restored 3 months after the wildfire.

• Korean Journal of Microbiology
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• v.49 no.2
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• pp.150-155
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• 2013

We have conducted pyrosequencing for freshwater microbial community analyses. Fourteen sites along the Yeongsan river were selected for this study, and samples were collected monthly from May to July, 2012. Total 987,380 reads were obtained from 42 samples and used for taxonomic classification and OTU distribution analysis. Our results showed that high geographical and temporal variation in the phylum level bacterial composition, suggesting that microbial community is a very sensitive parameter affected by the surrounding environments including tributaries and land use nearby. In addition, we conducted an OTU-based Microbial Source Tracking to identify sources of fecal pollution in the same region. From this study Firmicutes was found to be the most influential taxa in this region. Here, we report that the use of pyrosequencing based microbial community analysis may give an additional information on freshwater quality monitoring, in addition to the currently used water quality parameters, such as BOD and pH.

• Journal of Food Hygiene and Safety
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• v.24 no.3
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• pp.226-231
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• 2009

The aim of this study was to determine exposure assessment of pathogenic bacteria in edible ices by using the monitoring data from the previous study. According to the results of exposure assessment of edible ices contaminated with S. aureus, the contamination level of S. aureus in raw materials was higher than other foodborne pathogens, and the contamination level of S. aureus in mixed samples increased much before sterilization. The most significant reduction in contamination level was observed in mixed samples after sterilization, thus, the contamination levels in frozen final products was less than that of raw materials. Overall, the possibility for the infection of foodborne bacteria from the intake of edible ices per person per day was ranged from minimum $5.89{\times}10^{-7}$ to maximum $5.01{\tims}10^{-5}$. For more realistic estimates, consumption of edible ices and dose-response model must be studied further.

• The Journal of the Korean dental association
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• v.47 no.8
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• pp.522-533
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• 2009

Purpose: Infection with HIV-1 virus has become a critical worldwide public health problem. The oral complications of HIV infection with its progression of impairment of the host response to combat infection present unique challenges to the periodontists. Material and Methods : Medline research was carried out to find relationship of the progression of HIV infection to the occurrence of oral lesions including the HIV-related periodontal diseases. Results: The linear gingival erythema, necrotizing ulcerative periodontitis, necrotizing ulcerative gingivitis and oral candidiasis are common lesions in HIV-infected individuals. The linear gingival erythema and necrotizing ulcerative periodontitis lesions in HIV-infected subjects were found to have a similar microbiological profile. There are several general considerations in the periodontal management of the HIV-infected patient with or without periodontal disease. The altered immunity and host response in patients with HIV infection may also affect the incidence and severity of other common forms of periodontal disease not associated with HIV infection. Conclusion: Periodontal diseases in HIV-infected individuals present unique challenges in diagnosis, monitoring, treatment and maintenance. Therefore exact HIV staging, geographic location, antiviral and antimicrobial therapies and oral habits should be taken into consideration when treating HIV-infected patients.

• Korean Journal of Veterinary Research
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• v.40 no.3
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• pp.611-625
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• 2000

For the improvement of quality control of laboratory mouse, we investigated the environmental condition, histopathological findings and serological test using ELISA to mouse hepatitis virus(MHV), Mycoplasma pulmonis(MP), Clostridium piliforme(TZ) and Sendai virus (HVJ) of ICR, C57BL/6, CBA and C3H/He mice that were supplied from conventional laboratory animal facility. 1. The ammonia concentration of facility was below the recommended concentration, 15ppm, by the KNIH, and the room temperature($21{\sim}23^{\circ}C$) and relative humidity(40~60%) was optimum range recommend by the Ministry of Health and Welfare, respectively. 2. The incidence rate of inapparent disease was 86.6% and the major findings in the liver were vacuolar degeneration with nucleic pleomorphism. The lung was shown the thickening of alveolar wall and interstitial pneumonia with congestion. The kidney and spleen were observed the mild congestion and extramedullary hematopoiesis, respectively. 3. The positive reaction rates against MHV and MP in serological test was 97.9% and 37.5%, respectively but HVJ and TZ were negative. These results suggest that laboratory mice could be infected with MHV and MP under conventional environments. Therefore we recommend to select thoroughly inapparent infected mice and to convert conventional system into SPF facility as soon as possible.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.8
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• pp.3517-3522
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• 2011

Contamination of public bath water by waterborne pathogens can cause disease outbreaks and contribute to background rates of disease. The aim of this study is to determine the prevalence of waterborne pathogens in public baths. A total of 30 water samples were collected from 30 different public baths in seoul, Korea. Pathogens in water samples were concentrated by 0.45 ${\mu}m$ nitrocellulose membrane filter, analyzed by both cultivation and polymerase chain reaction-reverse blot hybridization (PCR-REBA) of partial 16S rRNA gene. Various microorganisms including Escherichia coli and Shigella spp. were identified by microbiological cultivation. E. coli, Shigella spp., Salmonella spp., Pseudomonas spp. and Mycobacterium spp. were identified by PCR-REBA. Our results suggest that appropriate hygiene practice and continuous monitoring is needed for reducing health risk associated with public bath houses.

• Journal of Food Hygiene and Safety
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• v.19 no.4
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• pp.185-192
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• 2004

Generic HACCP models for bakery products may help HACCP implementation at the wholesale bakery production lines easier. When baking, the internal temperature of bakery products went up to $85^{\circ}C$, which resulted in gelatinization of starch. Considering the characteristics of bakery products, general sanitation control procedures are the main target tool to keep bakery products safe. Monitoring of pathogenic microorganisms at bakery plant environment including production lines was carried out. At the wholesale bakery environment pathogenic microorganisms were detected. It gave a clue that general sanitation control procedures should be implemented for safe bakery products supply. Hazard analysis of raw materials and processing of bakery products, and determination of critical control points and critical limits at the wholesale bakeries lead to present generic model of bakery product HACCP plan. CCPs for the wholesale bakery products may be applied and modified for the implementation of HACCP plan at the wholesale bakery plant.

• Journal of Microbiology
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• v.43 no.3
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• pp.257-259
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• 2005

Although automated continuous-monitoring blood culture systems are both rapid and sensitive, false-positive and false-negative results still occur. The objective of this study, then, was to evaluate negative results occurring with BacT/Alert 3D blood culture systems. A total of 1032 samples were cultured with the BacT/Alert 3D automated blood culture system, using both aerobic (BPA) and anaerobic (BPN) media, and 128 of these samples yielded positive results. A total of 904 negative blood samples were then subcultured in $5\%$ sheep blood agar, eosin methylene blue, chocolate agar, and sabouraud-dextrose agar. Organisms growing on these subcultures were subsequently identified using both Vitek32 (bioMerieux, Durham, NC) and conventional methods. Twenty four $(2.6\%)$ of the 904 subcultures grew on the subculture media. The majority $(83.3\%)$ of these were determined to be gram-positive microorganisms. Fourteen $(58.3\%)$ were coagulase-negative staphylococci, two $(8.3\%)$ were Bacillus spp., one $(4.2\%)$ was Staphylococcus aureus, and one $(4.2\%)$ was identified as Enterococcus faecium. Streptococcus pneumoniae and Neisseria spp. were isolated together in two $(8.3\%)$ vials. Gram-negative microorganisms comprised $12.5\%$ of the subcultures, of which two $(8.3\%)$ were found to be Pseudomonas aeruginosa, and one $(4.2\%)$ was Pseudomonas fluorescens. The other isolate $(4.2\%)$ was identified as Candida albicans. We conclude that the subculture of negative results is valuable in the BacT/Alert 3D system, especially in situations in which only one set of blood cultures is taken.

• The Journal of Engineering Geology
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• v.20 no.1
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• pp.1-12
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• 2010

The objective of this study was to examine the hydrogeochemical and microbiological characteristics for stable maintenance of coastal LPG storage cavern. Cavern seepage water and groundwater in the vicinity of the LPG storage cavern were sampled and analyzed (February, May, August and October 2007). Groundwater samples of propane cavern showed high pHs of 8.1~12.4 due to dissolution of cement grouting materials that had been applied during the well and cavern construction. The EC values showed distinctive seasonal variation. The negative ORP indicated reduced condition. The seepage and surrounding groundwater are classified as Na-Cl type, which represents seawater effects. All of aerobic bacteria, anaerobic bacteria, slime forming bacteria and sulfate reducing bacteria were less than 500 CFU/mL, which indicated that there was no abrupt increase of bacteria in the cavern. Therefore there exist no hydrochemical symptoms to indicate unstable conditions of the cavern operation. However, regular and continuous monitoring is essentially required.

• Journal of Microbiology
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• v.39 no.4
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• pp.286-292
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• 2001

During mitosis. the proper segregation of duplicated chromosomes is corrdinated by a spindle check-point. The bifurcated spindle checkpoint blocks cell cycle progression at metaphase by monitoring unattached kinetochores and inhibits mitotic exit in response to the misorientation of the mitotic spin- dle Ibd1p/Bfa1p is a spindle checkpoint regulator of budding yeast in the Bub2p checkpoint pathway for mitotic exit and its disruption abolishes mitotic arrest when proper organization of the mitotic spin-dls inhibited. Ibd1p/Bfa1p localizes to the spindle pole body, a microtublue-organizing center in yeast, and its overexpression arrests the cell cycle in 80% of cells with an enlarged budy at mitosis and in 20 % of cells with multiple buds. In this study, we found that the C-terminus of Ibd1p/Bfa1p phys-ically interacts with Skp1p, a key component of SCF (Skp1/cullin/F-box) complex for ubiquition-medi-ated proteolysis of cel cycle regulatores as well as an evolutionally conserved kinetochore protein for cell cycle progression. A putative F-box motif was found in the C-terminus of Ibd1p/Bfa1p and its function was investigated by making mutants of conserved residues in the motif. These Ibd1p/Bfa1p mutants of a putative F-box interacted with SKp1p in vitro by two-hybrid assays as wild type Ibd1p/Bfa1p. Also these Ibd1p/Bfa1p utants displayed the overexpression phenotypes of wild type Ibd1p, when over-expressed under inducible promoters . These results suggest that a putative F-box motif of Ibd1p/Bfa1p is not essential for the interaction with SKp1p and its function in mitotic exit and cytokinesis.