• Journal of Yeungnam Medical Science
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• v.5 no.1
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• pp.49-60
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• 1988

Reviewing the results of the blood cultures performed at Yeungnam University Hospital during 4-year-period through January. 1, 1984 to December 31, 1987, the following results were obtained. 1) Out of 808:3 blood specimens cultured microorganisms grew in 582 specimens with positivity rate of 7.20%. Polymicrobial bacteremia was found in 16 patients. 2) Among 582 positive specimens, Gram-positive cocci grew in 189 specimens, and Gram-negative bacilli, in 393 specimens. Clinically significant microorganisms consisted of 82 Staphylococcus aureus, and 20 Strptococcus species in Gram-positive cocci group, 80 Salmonella typhi, 72 Escherichia coli, 72 Salmonella paratyphi A in Enterobacteriaceae, and 46 Pseudomonas cepacia, and 16 Pseudomonas aeruginosa in glucose non-fermentating microorganisms. 3) Increasing incidence of Serratia, Acinetobacter and Pseudomonas species as major nosocomial infection source is noteworthy. They showed increased tendency from 6.3% of 1984 to 17.7% of 1987 of total positive blood cultures. 4) High isolation rate of Pseudomonas species and Aeromonas hydrophilia was noted in summer, while Salmonella typhi showed high prevalence from May to September and in January. 5) In susceptibility tests of isolated organisms, staphylococcus aureus was sensitive to basic antimicrobial agents except for ampicillin. The glucose non-fermentating microorganisms showed high resistance to basic antimicrobial agents in 32.2%. In conclusion, considering the relatively higher incidence of growth of Staphylococcus epidermidis than ideal level indicates that sampling technique should be improved. Secondly, all the hospital staffs in cooperation with Hospital Infection Committee are desirable to pay efforts to decrease the nosocomial infection.

• Journal of Yeungnam Medical Science
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• v.9 no.2
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• pp.248-255
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• 1992

Eight bacterial strains were examined whether they have phoP/phoQ genes which were known to be involved in the intracellular survival of Salmonella typhimurium. The phoP/phoQ operon were known to sense the stimuli of the genes involved in the adaptation of the environment. Using 514-basepairs EcoRV DNA fragment of phoP region of Salmonella typhimurium as a probe, dot blot hybridization were performed. Chromosomal DNAs of Klebsiella pneumoniae, Pseudomonas aeruginosa, Serratia marscescens, Enterobacter cloacae, Salmonella typhimurium, Escherichia coli, Shigella dysenteriae, and Listeria monocytogenes were examined by DNA hybridization assay. Against our expectation, intracellular pathogen, L. monocytogenes, did not have similar DNA sequences to phoP/phoQ of S. typhimurium, while E. coli, S. dysenteriae, and E. cloacae showed the positive signal even though they were not intracellular pathogens. This result suggested that the phoP/PhoQ operon was absent in intracellular pathogenic bacterias other than S. typhimurium. Rather it was found in phylogenetically closer bacterias to S. typhimurium, which were not able to survive in intracellular environment. Some different mechanism, which is not dependent on phoP/PhoQ operon, could be involved in the intracelluar survival of L. monocytogenes.

• Microbiology and Biotechnology Letters
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• v.35 no.1
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• pp.1-10
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• 2007

The 44 endophytic bacterial strains were isolated from surface-sterilized root of rice cultivated in seven different locations of Chungcheong province, Korea. Each isolate was introduced into rice seedlings grown gnotobiotically by inoculating scissor-cut first true leaf with cell suspensions, and the colonization capacity of each isolate in root tissue was analyzed at 7 days after inoculation. Sixteen out of 44 isolates were re-isolated from root successfully with the frequency of $10^{3-5}$ CFU/g tissue. Interestingly, seven out of 16 isolates were identified as Burkholderia species. The identity between inoculated strains and re-isolates was confirmed by genomic finger-printing and 16S rDNA sequence analysis. By a confocal laser scanning microscopic observation it was revealed that KJ001 strain, one of the sixteen isolates tagged with gfp colonized in root tissue especially around xylem. Six out of seven Burkholderia strains obtained in this study showed antagonizing activities against seven different fungal pathogens, contain nifH gene, and five of them enhanced growth of cucumber over 30%. The isolates showed no hypersensitive response on tobacco leaves and no pathogenecity in rice. From these results it was found that the endophytic Burkholderia strains will be useful in agriculture to develop a biocontrol agent or a bio-fertilizer.

• Journal of Microbiology and Biotechnology
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• v.27 no.8
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• pp.1392-1400
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• 2017

Galactooligosaccharides (GOSs) are known to be selectively utilized by Bifidobacterium, which can bring about healthy changes of the composition of intestinal microflora. In this study, ${\beta}-GOS$ were synthesized using bifidobacterial ${\beta}-galactosidase$ (G1) purified from recombinant E. coli with a high GOS yield and with high productivity and enhanced bifidogenic activity. The purified recombinant G1 showed maximum production of ${\beta}-GOSs$ at pH 8.5 and $45^{\circ}C$. A matrix-assisted laser desorption ionization time-of-flight mass spectrometry analysis of the major peaks of the produced ${\beta}-GOSs$ showed MW of 527 and 689, indicating the synthesis of ${\beta}-GOSs$ at degrees of polymerization (DP) of 3 and DP4, respectively. The trisaccharides were identified as ${\beta}-{\text\tiny{D}}$-galactopyranosyl-($1{\rightarrow}4$)-O-${\beta}-{\text\tiny{D}}$-galactopyranosyl-($1{\rightarrow}4$)-O-${\beta}-{\text\tiny{D}}$-glucopyranose, and the tetrasaccharides were identified as ${\beta}-{\text\tiny{D}}$-galactopyranosyl-($1{\rightarrow}4$)-O-${\beta}-{\text\tiny{D}}$-galactopyranosyl-($1{\rightarrow}4$)-O-${\beta}-{\text\tiny{D}}$-galactopyranosyl-($1{\rightarrow}4$)-O-${\beta}-{\text\tiny{D}}$-glucopyranose. The maximal production yield of GOSs was as high as 25.3% (w/v) using purified recombinant ${\beta}-galactosidase$ and 36% (w/v) of lactose as a substrate at pH 8.5 and $45^{\circ}C$. After 140 min of the reaction under this condition, 268.3 g/l of GOSs was obtained. With regard to the prebiotic effect, all of the tested Bifidobacterium except for B. breve grew well in BHI medium containing ${\beta}-GOS$ as a sole carbon source, whereas lactobacilli and Streptococcus thermophilus scarcely grew in the same medium. Only Bacteroides fragilis, Clostridium ramosum, and Enterobacter cloacae among the 17 pathogens tested grew in BHI medium containing ${\beta}-GOS$ as a sole carbon source; the remaining pathogens did not grow in the same medium. Consequently, the ${\beta}-GOS$ are expected to contribute to the beneficial change of intestinal microbial flora.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.4
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• pp.396-402
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• 1996

This study was conducted to determine the effect of treatment with the plant-growth-promoting bacteria on the growth and yield of red pepper(Capsicum annuum L.) with different soil electrical conductivity(EC) levels. The mixed liquid culture was done pseudomonas P and saboraud dextrose medium. The isolated bacteria(IB) were inoculated by spray of 3.7ml at 1/2000a pot filled with different soil electrical conductivity level(2.9, 8.6, 11.5dS/m) every week, respectively, with mixed liquid culture (Pseudomonas P+Sabouraud dextrose) of eight strains. The plant height of red pepper with IBs treatment in different soil EC levels showed better growth than IBs nontreatment in the order of the 2.9>8.6>11.5 dS/m. The yield of pepper with IBs treatment in different soil EC level was higher in 13% than IBs nontreatment and chemical properties($P_2O_5$, K, Ca, Mg) of the soil after harvest in IBs treatment were slightly increased, while organic matter and EC of IBs treatment were slightly decreased than those of IBs nontreatment. Moisture content of the soil after the harvesting with IBs treatment was slightly increased than IBs nontreatment.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.5
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• pp.654-661
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• 2013

The current research is designed to analyze sterilization effects on mulberries in terms of storage temperature and storage period after treating with tap water (TW), electrolyzed water (EW) and aqueous chlorine dioxide ($ClO_2$). The treated $ClO_2$ concentrations are 10, 50, 100 and 200 ppm. In each concentration, the mulberries are soaked for 30 seconds respectively. The sterilization effects are being compared at room temperature ($25^{\circ}C$) and at $4^{\circ}C$, respectively. And the enzyme activity related to quality is also being investigated and analyzed about for browning inhibition effects. Microbial sterilizing power increases more in treating plots with EW and $ClO_2$ than treating plot with TW. Futhermore sterilizing power of $ClO_2$ increased sharply on high concentration treatment plot as well. Sterilization effects of $ClO_2$ during storage time are better at cold temperature. Pictures taken from scanning electron microscope reveal that there are no microbes in sterilizing solutions treatment plots. From measurement of the enzyme activity, it is concluded that activities decrease more in sterilizing solutions treatment plots as comparing with TW treated plot during the time. The amount of total polyphenolics decrease with the time passing and EW and $ClO_2$ treatment shows less contents than TW treatment. Thus, EW and $ClO_2$ treatment of mulberris are considered as method to improve safety by reducing total plate count and to contribute to quality maintenance and to extend storage time.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1432-1438
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• 1998

The gamma-radiation sensitivity of eight kinds of pathogenic bacteria related to beef was investigated in frozen cells $(-18^{\circ}C)$ with 0.1 M phosphate buffer and inoculated cells in beef. In frozen cells, D10 values of pathogenic bacteria related to beef were $0.07{\sim}0.69$ kGy, and inactivation factors were $2.90{\sim}42.86$ at the radiation doses of $2{\sim}3$ kGy. Beef was inoculated with Escherichia coli, Pseudomonas aeruginosa, Salmonella typhimurium, Enterobacter aerogenes, Vibrio parahaemolyticus, Staphylococcus aureus, Listeria monocytogenes, and Aeromonas hydrophila. Inoculated beef samples were packaged in air and irradiated at 0.005 to 3.0 kGy. Ninety percent of the viable pathogenic bacteria in beef was eliminated by doses of $0.1{\sim}0.61$ kGy at room temperature, and the inactivation factors were $3.28{\sim}30.0$ kGy at the radiation doses of $2{\sim}3$ kGy. Therefore, irradiation is considered to be an effective method to control pathogenic bacteria in beef.

• The Journal of Korean Academy of Prosthodontics
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• v.37 no.6
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• pp.741-755
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• 1999

As a material of metal-ceramic prosthesis, nickel as a form of Ni-Cr alloy has been used for many dental prostheses in many cases. However, several problems in use of the alloy have been revealed (ex : tissue stimulation, skin allergy, hypersensitivity, cytotoxicity and carcinogenecity). Little is known about nickel with respect to the relationship between Ni-prosthesis and gaining of Ni-resistance in oral microorganisms. The present study was undertaken to check wheather use of Ni-prosthesis leads to occurrence of Ni-resistant microorganisms. So this study may suggest the possible relationships between the oral microorganisms and nickel-resistance in oral environment. Bacteria were isolated from the gingival crevicular fluid on the pateints wearing Ni-Cr prosthesis. The isolated bacteria were tested for their Ni-resistance in nickel containing media at different concentration from 3mM to 110mM. E. coli HB101 was used as control. The Ni-resistant bacteria were isolated and biochemically identified. The Ni-resistant bacteria were tested several bio-chemical, molecular-biological tests. Performed tests were ; measuring the growth curve, antibiotic test, growth ability test in liquid media, isolation of the chromosome and plasmid, digestion of DNA by restriction enzyme, electrophoresis of chromosome and plasmid DNA, identification of Ni-resistant genes by the DNA hybridization. The results were as follows: 1) The bacteria isolated from gingival crevicular fluid on the patients wearing Ni-Cr alloy pros-thesis showed nickel-resistance. 2) The isolated microorganisms grew at nickel containing media of high concentrations (60mM-110mM). 3) Based on the biochemical tests, the isolated microorganisms were identified as Enterococcus faecalis(13 cases), Klebsiella pneumoniae(1 case) and Enterobacter gergeviae(1 case). 4) Enterococcus faecalis expressed not only nickel resistance but also the multi-drug resistance to several antibiotics ; chloramphenicol, kanamicin, streptomycin, lincomycin, clindamycin. However, all strain showed the sensitivity against the tetracycline. 5) DNA hybridization result suggest that there is no homology between the previousely known gene of nickel resistance in Klebsiella pneumoniae and chromosomal DNA of Enterococcus faecalis.

• Journal of Chest Surgery
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• v.21 no.2
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• pp.316-325
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• 1988

Author made a clinical study of 248 cases of pleural effusion patients who were diagnosed and treated at departments of chest surgery and internal medicine, Pusan National University Hospital, during the period from Jan. 1983 to Dec. 1985. The age distribution ranged from 1 to 76 years old and the ratio of male to female was 1.38:1. The cardinal symptoms were chest pain[69.4%], dyspnea[66.1%], cough[57.7%], fever[37.1%], sputum[26.2%], general malais[13.7%] and cyanosis[1.6%] in this order. The causes of pleural effusion were pulmonary tuberculosis[42.4%], pneumonia[23.0%], malignancy[16.5%], congestive heart failure[9.3%], liver cirrhosis[2.8%] and nephrosis[2.0%] in this order. The protein in the pleural effusions was 1.61*0.90[mean*SD] gm% in transudate and 5.05*1.10[Mean*SD] gm% in exudate. In 34 cases[89.5%]out of 38 transudates, the protein was under 3 gm% and in 201 cases [95.7%] out of 210 exudates, the protein was over 3 gm%. The protein ratio of pleural effusion to serum was 0.2650.11[Mean LSD] in transudates and 0.73*0.12[Mean LSD] in exudate. The ratio under 0.5 was in 36 cases[94.8%] out of 38 transudates and over 0.5 was in 206 cases[98.1%] out of 210 exudates. The LDH in the pleural effusion was 114.7550.3[mean*SD] units / ml in transudate and 627.05325.9[mean*SD] units / ml in exudate. The LDH less than 200 units / ml was in 36 cases[94.6%] out of 38 transudates and more than 200 units / ml was in 199 cases[94.7%] out of 210 exudates. The LDH ratio of pleural effusion to serum was 0.34k 0.11[mean*SD] in transudate and 1.15*1.12[mean*SD] in exudate. The LDH ratio of pleural effusion to serum was less than 0.6 in 36 cases[94.8%]out of 38 transudates and more than 0.6 in 200 cases[95.2%] out of 210 exudates. Etiologic organisms were confirmed in 78 cases[48.1%] among the requested 162 cases. In the 78 cases of etiologic organisms, staphylococcus was 33 cases[20.3%], streptococcus 24 cases[14.8%], Klebsiella pneumonia 7 cases[4.3%], pseudomonas 6 cases[3.7%], E. coli[3.1%], enterobacter 3 cases[1.9%]. 43 patient of pleural effusion from malignancy were undergone three or more thoracenteses. In 13 cases[31.7%], three specimen were negative and in 7 cases[17.1%], three specimens were positive for malignancy. In the remaining of 21 cases[51.2%], malignant cells were found in one or more of the specimens but not in all. Methods of treatment of pleural effusion by closed thoracotomy was 188 cases[75.8%], thoracentesis 27 cases[10.9%], decortication 16 cases[6.5%], thoracoplasty 6 cases[2.4%] and decortication with thoracoplasty 3 cases[1.2%].

• Applied Biological Chemistry
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• v.40 no.2
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• pp.157-162
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• 1997

A novel compound, named YH-487, was synthesized by attaching the thiol and aminothiazole residue to $C_3$ and $C_7$ position of 7-aminocephalosporanic acid (7-ACA). The therapeutic efficacy on infected animals, pharmacokinetics in vivo and the effect on intestinal microflora of YH-487 were examined. The pharmacokinetics of YH-487 were similar to that of cefotaxime, a third generation ${\beta}-lactam$ antibiotics, in rat. Upon in vivo administration, YH-487 was predominantly delivered to kidney, and mostly excreted through kidney without making any metabolites. The therapeutic efficacy of YH-487 to animal infected with E. coli was three times and twenty times higher than that of cefotaxime and cefotiam, respectively, In vivo administration of YH-487 to Sprague-Dawley rats significantly decreased the population of intestinal gram negative species such as Enterobacteria and Barteroides. However, no significant changes were obseved in gram positive species such as Lactobacillus, Bifidobacteria and Staphylococcus. In addition, continuous administration of YH-487 did not increase the possibility to induce resistant strains in intestinal microflora.