• Journal of fish pathology
• /
• v.25 no.3
• /
• pp.263-270
• /
• 2012

This study surveyed for the prevalence of parasites, bacteria and viruses in four fish species, olive flounder (Paralichthys olivaceus), red sea bream (Pagrus major), black sea bream (Acathopagrus schlegeli) and black rockfish (Sebastes schlegeli) in 2010. The survey was aimed to compare the pathogens detected from wild and cultured fish for an epidemiological study. Anisakis sp. was predominantly detected from wild olive flounder and red sea bream (58.6% and 41.7% respectively), but not from the cultured fishes, suggesting anisakid infection is rare in cultured fish. The wild fish get in contact with the anisakids through their prey such as small fishes or crustaceans which carry the anisakids; whereas the cultured fish are fed with formulated feed, free of anisakids. Bacterial detection rates from the wild fishes examined in the study were lower than those of cultured fishes. Vibrio sp. dominated among detected bacterial population in cultured olive flounder (18%). Since vibriosis is known as a secondary infection caused by other stressful factors such as parasitic infections, handling and chemical treatment, it seems that cultured olive flounder are exposed to stressful environment. Viruses diagnosed in the study showed difference in distribution between wild and cultured fishes; hirame rhabdovirus (HRV) (0.1%) and lymphocystis disease virus (LCDV) (3.9%) were detected in the cultured olive flounder, but not in the wild fish, and marine birnavirus (MBV) (1.7%) and red sea bream iridovirus (RSIV) (3.2%) were detected from the wild and cultured red sea bream, respectively. From the survey conducted, it can be concluded that even though some pathogens (Trichodina sp., Microcotyle sp., etc.) are detected from both the wild and cultured fish, pathogens such as Anisakis sp., Vibrio sp. and LCDV showed difference in distribution in the wild and cultured host of same fish species and this can be attributed to their environmental condition and feeding.

• Tuberculosis and Respiratory Diseases
• /
• v.47 no.3
• /
• pp.321-330
• /
• 1999

Background : Early diagnosis and proper antibiotic treatment are very important in the management of ventilator-associated pneumonia (VAP) because of its high mortality. Bronchoscopy with a protected specimen brush (PSB) has been considered the standard method to isolate the causative organisms of VAP. However, this method burdens consumer economically to purchase a PSB. Another useful method for the diagnosis of VAP is quantitative cultures of aspirated specimens through bronchoscopic bronchoalveolar lavage (BAL), for which the infusion of more than 120 m1 of saline has been recommended for adequate sampling of a pulmonary segment. However, occasionally it leads to deterioration of the patient's condition. We studied the diagnostic efficacy of minibronchoalveolar lavage (miniBAL), which retrieves only 25 ml of BAL fluid, in the isolation of causative organisms of VAP. Methods: We included 38 consecutive patients (41 cases) suspected of having VAP on the basis of clinical evidence, who had received antibiotics before the bronchoscopy. The two diagnostic techniques of PSB and miniBAL, which were performed one after another at the same pulmonary segment, 'were compared prospectively. The cut-off values for quantitative cultures to define causative bacteria of VAP were more than $10^3$ colony-forming units (cfu)/ml for PSB and more than $10^4$ cfu/ml for BAL. Results: The amount of instilled normal saline required to retrieve 25 ml of BAL fluid was $93{\pm}32 ml$ (mean${\pm}$SD). The detection rate of causative agents was 46.3% (19/41) with PSB and 43.9% (18/41) with miniBAL. The concordance rate of PSB and miniBAL in the bacterial culture was 85.4% (35/41). Although arterial blood oxygen saturation dropped significantly (p<0.05) during ($92{\pm}10%$) and 10 min after ($95{\pm}3%$) miniBAL compared with the baseline ($97{\pm}3%$), all except 3 cases were within normal ranges. The significantly elevated heart rate during ($l25{\pm}24$/min, p<0.05) miniBAL compared with the baseline ($1l1{\pm}22$/min) recovered again in 10 min after ($111{\pm}26$/min) miniBAL. Transient hypotension was developed during the procedure in two cases. The procedure was stopped in one case due to atrial flutter. Conclusion: MiniBAL is a safe and effective technique to detect the causative organisms of VAP.

• Journal of Food Hygiene and Safety
• /
• v.31 no.4
• /
• pp.258-263
• /
• 2016

The risks of sanitary indicative bacteria, heavy metals and chlorinated derivatives in 94 cases of sanitary wet towels used in food services (39 from sanitary wet towel treatment business, 55 from food services) were assessed in the present study. Lead was detected in the range of N.D.~0.41 mg/kg (75 cases were not detected), N.D.~0.25 mg/kg of arsenic (93 cases were not detected), N.D.~0.01 mg/kg of cadmium (7 cases were lower than limit of quantitation; 87 cases were not detected), 0.003 mg/kg ~ 0.09 mg/kg of mercury. And chromium (VI) was not detected from all samples. The level of lead was the highest among the tested heavy metals, and the highest concentration of lead was 0.41 mg/kg. However, it was only 2.1% of legal limit (less than 20 mg/kg). The average moisture content of the samples was 61.9% (50.0% ~ 77.0%) and it showed no relevance to the detection of bacterial counts. Escherichia coli was not detected. Bacterial counts were detected 43 cases and among them, 24 cases were exceeded the legal limit. It was verified that the packaging conditions of sanitary wet towel (whether it is packed by a piece or not and sealed or not) are critical factors to cause the germ contamination and cross contamination in the wet towels. The chlorinated derivatives (chlorites and chlorates) were detected in 17 (19.3%) out of 88 cases. The results would be used as preliminary information to establish the programs of "Safety education for manufacturers and public policy of safety".

• Food Science of Animal Resources
• /
• v.23 no.2
• /
• pp.161-167
• /
• 2003

Identification of salmonellosis-infected commercial poultry flocks has become a pivotal component of efforts to reduce incidence of egg-associated transmission of S. enteritidis and S. typhimurium to humans. As a basic study for sanitary control of S. enteritidis and S. typhimurium, main food-borne pathogenic bacteria in eggs produced by domestic hens, commercial egg samples were tested for specific antibodies to whole cells of S. enteritidis and S. typhimurium and outer membrane protein(OMP) of S. typhimurium by ELISA to detect infection of S. enteritidis and S. typhimurium in various groups of hens. When the antibody titers of yolks from three commercial brand eggs were tested after diluting in the ratio from 1:100 to 1:1,600 with double dilution method, ELISA values of the specific antibodies could be shown as differences in dilution patterns by comparing with negative control egg. When the antibody titers of the yolks from two commercial brand eggs were tested after diluting in the ratio of 1:200 and 1:1,000, ELISA values of specific antibodies were different among same brand eggs. When the antibody titers of yolks from five eggs sampled randomly from twenty one commercial brand eggs were tested after diluting in the ratio of 1:1,000, ELISA value of the specific antibodies were shown generally high. ELISA values of 28.5, 30, and 28.5% of yolks from 21 brand eggs were shown low and similar to negative control egg in antibody titers to whole cells of S. enteritidis and S. typhimurium and OMP of S. typhimurium, respectively. The results demonstrated that ELISA test of egg yolk antibody could provide a highly sensitive indicator to detect contamination of S. typhimurium and S. enteritidis in poultry, and could be used effectively to reduce incidence of S. typhimurium and S. enteritidis infection in poultry.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
• /
• 2001.06a
• /
• pp.1031-1031
• /
• 2001

The mammary gland is made up of remarkably sensitive tissue, which has the capability of producing a large volume of secretion, milk, under normal or healthy conditions. When bacteria enter the gland and establish an infection (mastitis), inflammation is initiated accompanied by an influx of white cells from the blood stream, by altered secretory function, and changes in the volume and composition of secretion. Cell numbers in milk are closely associated with inflammation and udder health. These somatic cell counts (SCC) are accepted as the international standard measurement of milk quality in dairy and for mastitis diagnosis. NIR Spectra of unhomogenized composite milk samples from 14 cows (healthy and mastitic), 7days after parturition and during the next 30 days of lactation were measured. Different multivariate analysis techniques were used to diagnose the disease at very early stage and determine how the spectral properties of milk vary with its composition and animal health. PLS model for prediction of somatic cell count (SCC) based on NIR milk spectra was made. The best accuracy of determination for the 1100-2500nm range was found using smoothed absorbance data and 10 PLS factors. The standard error of prediction for independent validation set of samples was 0.382, correlation coefficient 0.854 and the variation coefficient 7.63%. It has been found that SCC determination by NIR milk spectra was indirect and based on the related changes in milk composition. From the spectral changes, we learned that when mastitis occurred, the most significant factors that simultaneously influenced milk spectra were alteration of milk proteins and changes in ionic concentration of milk. It was consistent with the results we obtained further when applied 2DCOS. Two-dimensional correlation analysis of NIR milk spectra was done to assess the changes in milk composition, which occur when somatic cell count (SCC) levels vary. The synchronous correlation map revealed that when SCC increases, protein levels increase while water and lactose levels decrease. Results from the analysis of the asynchronous plot indicated that changes in water and fat absorptions occur before other milk components. In addition, the technique was used to assess the changes in milk during a period when SCC levels do not vary appreciably. Results indicated that milk components are in equilibrium and no appreciable change in a given component was seen with respect to another. This was found in both healthy and mastitic animals. However, milk components were found to vary with SCC content regardless of the range considered. This important finding demonstrates that 2-D correlation analysis may be used to track even subtle changes in milk composition in individual cows. To find out the right threshold for SCC when used for mastitis diagnosis at cow level, classification of milk samples was performed using soft independent modeling of class analogy (SIMCA) and different spectral data pretreatment. Two levels of SCC - 200 000 cells/$m\ell$ and 300 000 cells/$m\ell$, respectively, were set up and compared as thresholds to discriminate between healthy and mastitic cows. The best detection accuracy was found with 200 000 cells/$m\ell$ as threshold for mastitis and smoothed absorbance data: - 98% of the milk samples in the calibration set and 87% of the samples in the independent test set were correctly classified. When the spectral information was studied it was found that the successful mastitis diagnosis was based on reviling the spectral changes related to the corresponding changes in milk composition. NIRS combined with different ways of spectral data ruining can provide faster and nondestructive alternative to current methods for mastitis diagnosis and a new inside into disease understanding at molecular level.

• Clinical and Experimental Pediatrics
• /
• v.46 no.6
• /
• pp.561-565
• /
• 2003

Purpose : Urinary tract infection(UTI) is the most common bacterial infectious disease that may induce severe renal injury unless early diagnosis and appropriate treatment are performed. If recurrent UTI is prevented, renal injury can be also reduced. Therefore, we studied the risk factors of recurrent UTI in children. Methods : We performed a retrospective study of 168 children(58 girls and 110 boys) who were treated for UTI in the Department of Pediatrics, Korea University Medical Center, during 2000-2001. Among 168 children, 93 children were followed up for more than six months. For the detection of recurrence of UTI, we performed monthly routine urine cultures and physical examinations. Results : The total rate of recurrence was 32.3%. The recurrent rate in boys and girls were 37.1% and 17.4%, respectively(P<0.05). The most common causative bacteria in the first onset and in recurrence were Escherichia coli. There was a significant difference in the onset age of UTI between boys with recurrence($4.8{\pm}1.0months$) and without recurrence($16.5{\pm}3.8months$)(P<0.01). In 77% of cases, urinary tract infection recurred within six months of the first infection. The time of the first recurrence after UTI was $3.7{\pm}0.6months$ in boys and $14{\pm}8.2months$ in girls(P<0.01). The number of recurrences showed a significant difference between the group under the age of one year($0.69{\pm}0.8/year$) and those above the age of one year($0.16{\pm}0.4/year$)(P<0.05). There was no difference in the recurrent rate between those with structural abnormality and those with normal anatomy. Conclusion : Monthly routine urine cultures are efficient in detecting recurrent UTI in children. Because the male sex and young age especially less than one year of age are risk factors for increased recurrence rate of UTI, these children should be followed-up with urine cultures.

• Restorative Dentistry and Endodontics
• /
• v.33 no.6
• /
• pp.537-544
• /
• 2008

Polymerase chain reaction (PCR) can detect bacteria more rapidly than conventional plate counting. However DNA-based assays cannot distinguish between viable and dead cells due to persistence of DNA after cells have lost their vitality. Recently, propidium monoazide (PMA) treatment has been introduced. The purpose of this study is to evaluate the applicability of the PMA treatment and real-time PCR method for cell counting in comparison with plate counting and to evaluate the antibacterial efficacy of 2% CHX on E. faecalis using PMA treatment in combination with real-time PCR. Firstly, to elucidate the relationship between the proportion of viable cells and the real-time PCR signals after PMA treatment, mixtures with different ratios of viable and dead cells were used. Secondly, relative difference of viable cells using PMA treatment in combination with real-time PCR was compared with CFU by plate counting. Lastly, antibacterial efficacy of 2% CHX on E. faecalis was measured using PMA treatment in combination with real-time PCR. The results were as follows : 1. Ct value increased with decreasing proportion of viable E. faecalis. 2. There was correlation between viable cells measured by real-time PCR after PMA treatment and CFU by plate counting until Optical density (OD) value remains under 1.0. However, viable cells measured by real-time PCR after PMA treatment have decreased at 1.5 of OD value while CFU kept increasing. 3. Relative difference of viable E. faecalis decreased more after longer application of 2% CHX.

• The Korean Journal of Pesticide Science
• /
• v.10 no.2
• /
• pp.76-83
• /
• 2006

In order to investigate the impacts of non-selective herbicide, glufosinate-ammonium (ammonium 4-[hydroxy(methyl)phosphinoyl] -DL-homoalaninate, GLA) to the non-target organisms, earthworm was exposed to GLA in the field soil for a month, and microbial populations in the soil were investigated after application of GLA. Simultaneously, the residues of GLA and its metabolite, 3-MPP were analyzed in the same soil. Meanwhile, to elucidate the influence of GLA to the growth of non-target crops incase of inter-furrow application, the amounts of carotenoid, chlorophyll, amino acid, proteins and sugars in the leaves of potato and chinese cabbage grown in the same field were investigated. In result, the dead earthworm was not observed during the test period, and the increasing rates of bodyweight were $9.410{\sim}11.603%$ in GLA-treated plots and 5.645% in GLA-untreated plots. The populations of fungi, bacteria and actinomycetes in the GLA-treated soils were $6.2{\times}10^4$, $1.5{\times}10^6$ and $5.7{\times}10^4$, respectively. They maintained relatively similar levels to the control which were $3.7{\times}10^4$, $3.7{\times}10^5$ and $3.7{\times}10^4$, respectively. In residue analysis, the limit of detection of GLA was 0.02 mg $kg^{-1}$, that of 3-MPP was the same level, and the half-life of GLA was 15 days in sandy clay loam soil. This result indicates that GLA was degraded very quickly in field soil. On the other hand, the amounts of physiological, biochemical components such as carotenoid, amino acid, chlorophyll, protein and sugar were ranged from 90.0 to 104.3% in potato and from 99.0 to 112.7% in chinese cabbage. Comparing with hand-weeded plots, it is indicated that GLA had not affected to the growth of non-target crops when applied at inter-furrow in crops-growing field.

• Journal of Dairy Science and Biotechnology
• /
• v.33 no.2
• /
• pp.119-127
• /
• 2015

To date, detection of microbial populations in dairy products has been performed using culture media, which is a time-consuming and laborious method. The recently developed chromogenic media could be more rapid and specific than classical culture media. However, the newly developed molecular-based technology can detect microbial populations with greater rapidity and sensitivity than the classical method involving culture media and chromogenic media. This molecular-based technology could provide various options for monitoring the characterization of different states of bacteria and cells. Thus, it could help upgrade the processing system of the dairy industry so as to maintain the safety and quality of dairy foods. Among the various newly developed molecular-based technologies, flow cytometry can potentially be used for monitoring microbiological populations in the dairy industry if official international standards are available for this purpose. When omics technology would have biomarker identification, it could be regarded as the rapid and sensitive analytical methods. Methods based on PCR, which has become a basic technique in microbiological research, can be developed and validated as alternative methods for quantification of dairy microorganisms. This review discusses methods for monitoring microbiological populations in dairy foods and the limitations of these studies, as well as the need for further research on such methods in the dairy industry.

• Journal of Food Hygiene and Safety
• /
• v.28 no.3
• /
• pp.279-285
• /
• 2013

To establish sample preparation method for detection of food-borne pathogens from lettuce, perilla leaves, cucumber, pepper, and cherry tomato, the influences of diluent composition, processing time, and proportion of diluent to sample were examined. Each produce was inoculated with 6.0 log $CFU/cm^2$ of Escherichia coli O157:H7, Salmonella Typhimurium, Listeria monocytogenes, Staphylococcus aureus, and Bacillus cereus. Each produce was treated with 0.1% peptone water, and D/E neutralizing broth. Processing time of produce was 30, 60, 90, and 120s, and the proportion of diluent to sample was 2 : 1, 4 : 1, 9 : 1, and 19 : 1. The number of bacteria after treatment of D/E neutralizing broth was higher than that of 0.1% peptone water (P<0.05). In cherry tomato, the population of S. typhimurium recovered from treated with D/E broth was higher than that recovered from treated with 0.1% peptone water by 1.05 log $CFU/cm^2$ (P<0.05). No difference in numbers of pathogens was observed in processing time. Optimum proportion of diluent to perilla leaf, iceberg lettuce, cucumber, green pepper, and tomato was 9 : 1, 4 : 1, 2 : 1, 2 : 1, and 2 : 1, respectively. These data suggest that D/E neutralizing broth should be recommend as diluent, and the diluent volume applied to produce should be determined in proportion to produce surface area per weight (g).