• Korean Journal of Microbiology
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• v.42 no.4
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• pp.257-264
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• 2006

Fifty eight Cryptococcus neoformans strains isolated from clinical and environmental sources in Korea were examined for their serotypes and extracellular enzyme activities. Among the 51 strains isolated from clinical sources, 48 strains were serotype A (94.1%), 2 strains were serotype B (3.92%), and 1 strain was serotype D (1.96%). All seven environmental strains isolated from pigeon excreta were identified as serotype A. All isolates of C. neoformtans were positive for the production of extracellular proteinase and phospholipase. In the API-ZYM system, all fifty eight isolates produced alkaine phosphatase, esterase C4, esterase lipase: C8, leucine arylamidase, acid phosphatase, naphthol-AS-BI-phosphohydrase, $\alpha$-glucosidase and $\beta$-glucosidase. Thirty nine isolates (67.2%) of C. neoformans produced N-acetyl-$\beta$-glucosidase. Two isolates, serotype B, and B only one serotype A produced $\beta$-glucuronidase. Analysis of enzymatic profiles to 21 enzymes revealed four biotypic patterns among the 58 strains. The enzymatic patterns of C. neoformans isolated from clinical and environmental sources represented a significant relationship with the serotypes.

• Korean Journal of Clinical Laboratory Science
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• v.39 no.1
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• pp.49-55
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• 2007

HCV is a single-stranded RNA virus and more than 1 million new cases are reported annually worldwide. The six major HCV genotypes and numerous subtypes vary in their geographic distribution. It is thought that genetic heterogeneity of HCV may account for some of the differences in disease outcome and response to treatment observed in HCV infected persons. In this study, we determined HCV genotypes among chronic Korean HCV patients and evaluated direct sequence PCR protocols developed. For the study, 232 chronic HCV patient sera were used. HCV RNA was extracted and two pairs of consensus PCR primers were selected in 5'UTR region for amplification of HCV RNA. Amplification products obtained from the HCV positive cases were subjected to automatic sequencing. Sequences were compared with those in GenBank by using the BLAST program. From this study, five HCV genotypes, 1b, 2a, 2b, 2c and 3a were found. HCV genotypes 4, 5 and 6 were not determined. HCV genotype 1b (53.9%, 125/232) and 2a (35.8%, 83/232) were most frequently found. This group was followed by 2b (3.9%, 9/232), 3a (3.4%, 8/232) and 2c (3.0%, 7/232). The data presented here suggest a complex distribution of HCV types and they were well correlated with other reports on Koreans and will be helpful for type-specific follow-up of Korean HCV patients. This study showed that 5'UTR direct sequence analysis is a sensitive and rapid method to identify HCV genotypes.

• Food Science and Preservation
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• v.12 no.4
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• pp.355-360
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• 2005

This study was carried out to research the use of tar colors in children's favorite foods such as candies, soft drinks, chewing gums, cereals, and ice bars in order to acquire basic data on food safety. The tar colors were simultaneously analyzed by high performance liquid chromatography (HPLC). The contents of tar colors in candies, soft drinks, gums, cereals, and ice bars were maximum 74.10 mg/100 g, 5.96 mg/100 g, 35.70 mg/100 g, 20.10 mg/100 g, and 4.93 mg/100 g, respectively. In addition, every tar colors except for Indigo carmine (B2) and Fast Green FCF (G3) among permitted tar colors were used in foods and more than two kinds of tar colors were used in most cases. From the results, only types of tar colors for foods were regulated, but the amount was not regulated.

• Journal of Food Hygiene and Safety
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• v.32 no.1
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• pp.57-63
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• 2017

Foreign materials with a variety of types and sizes are found in food; thus, extraordinary efforts and various analytical methods are required to identify the types of foreign materials and to find out accurate causes of how they unintentionally enter food. In this study, human, cow, pig, mouse, duck, goose, dog, and cat were chosen as various types of animal hairs because they can be frequently incorporated into food during its production or consumption step. We morphologically analyzed them using stereoscopic, optical, SUMP method, and scanning electron microscopes, showing differences in each type. In addition, X-ray fluorescence spectrometer (XRF) was used to analysis chemical compositions ($^{11}Na{\sim}^{92}U$, Mass%) of samples. As a result, we observed that mammalian hairs were mainly composed of sulfur. Organic compounds of samples were further analyzed by fourier transform infrared spectroscopy (FT-IR) that can compare spectra of given materials; however, this method did not show significant differences in each sample. In this study, we suggest a rapid method for the identification of the causes and types of foreign materials in food.

• The Korean Journal of Nuclear Medicine Technology
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• v.15 no.2
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• pp.104-110
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• 2011

Purpose: The object evaluation method about medical institutes of these days increases credibility of consumers about medical services by conducting a certification system about medical institutes. In addition, as nuclear medicine test rooms and diagnosis test medicine room adopt many kinds of international certification systems, the matters regarding safety management of test rooms are being regarded as important. Since the blood test rooms of nuclear medicine are exposed to many harmful factors such as infection from clinical specimen and radioactive isotope reagent, there is a need to pay lots of attention to the safety management of staff and patients. Therefore, this study discusses safety management activities of staff and patients, which are conducted in the blood test rooms of the nuclear medicine department in Asan Medical Center. Materials and Methods: In the blood test rooms of the nuclear medicine department in Asan Medical Center, the matters regarding comprehensive safety management by the person in charge of safety management are offered and all staff members of the test rooms apply them into work. Safety management education is regularly conducted according to established regulations, and infection is prevented through implementation of wearing personal protectors and hand sanitation during test work. In addition, technical safety guides and accident guides for interruption of electric power are provided against emergencies. Through infection management guides, infection prevention and preparation methods for infection are learned and radioactive isotope management, safety management about reagent use and safety guides about harmful chemical substances are being applied to work. Results: The blood test rooms of the nuclear medicine department apply safety management regulations to work. Under the situation where hand sanitation should be conducted, hands are washed to prevent infection between staff and patients, and for preventing infection from clinical specimen, personal protectors are worn. The reagent, which is classified as harmful substance, is separately stored to be easily recognized, radioactive wastes and general medical wastes are also safely managed. Through these lots of safety management activities, safety management awareness of staff members is enhanced, and patients are protected from many dangers. Conclusion: Staff members of the blood test rooms of the nuclear medicine department should be fully aware of safety management regulations and apply them to work. When better safety management suggestions are made, they need to be examined and applied for increasing quality of safety management for staff and patients.

• Pediatric Infection and Vaccine
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• v.8 no.2
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• pp.199-205
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• 2001

Purpose : Since the first report of vancomycin-resistant enterococci(VRE) in 1986, the resistance to vancomycin in enterococci has been increasingly rapidly. In this study, we investigated the clinical manifestations of pediatric patients with VRE and the pattern of the antibiotic use with increasing the rate of VRE in pediatrics Methods : We studied retrospectively 36 pediatric patients who were isolated VRE from January 1998 to December 2000. We classified patients into ICU and non ICU groups and reviewed species of VRE, specimens in which VRE were first detected and procedures performed before VRE detected. Results : We have found that the number of pediatric patients isolated VRE is increasingly annually in this study. In addition, the number of VRE-isolation in the ICU group and in patients who were operated or who underwent active procedures is much higher than that of in the non ICU group and in patients who were taken medication only. Enterococcus faecium is the main species of VRE. VRE showed high resistance to almost all antibiotics except tetracycline, and resistance was closely related to the duration of hospitalization and history of the antibiotic use. The proportion of the cephalosporin use was higher than any other antibiotic before VRE detection. In contrast, that of teicoplanin was higher than any other antibiotic after VRE detection(P<0.05). The cases of superinfection is higher in the ICU group than in non ICU group. Conclusion : In the hospital level, prevention of nosocomial infection through proper administrative policies, through surveillance of high risk VRE regions and prudent antibiotic use can prevent VRE outbreaks and corresponding side effects.

• Pediatric Infection and Vaccine
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• v.21 no.3
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• pp.207-213
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• 2014

Purpose: This study aimed to investigate the association between respiratory virus infection and pneumococcal colonization in children. Methods: From May 2009 to June 2010, nasopharyngeal (NP) aspirates were obtained from patients under 18 years old who visited Seoul National University Children's Hospital for respiratory symptoms. NP samples were used to detect respiratory viruses (influenza virus A and B, parainfluenza virus 1, 2 and 3, respiratory syncytial virus A and B, adenovirus, rhinovirus A/B, human metapneumovirus, human coronavirus 229E/NL63 and OC43/HKU1) by RT-PCR and pneumococcus by culture. Results: Median age of the patients was 27 months old. A total of 1,367 NP aspirates were tested for respiratory viruses and pneumococcus. Pneumococcus was isolated from 228 (16.7%) of samples and respiratory viruses were detected from 731 (53.5%). Common viruses were rhinovirus (18.4%), respiratory syncytial virus (RSV) A (10.6%), adenovirus (6.9%), influenza virus A (6.8%). Pneumococcal isolation rate was significantly higher in the cases of positive virus detection than negative detection [21.3% (156/731) vs. 11.3% (72/636), P <0.001]. For individual viruses, pneumococcal isolation rate was positively associated with detection of influenza virus A [24.7% (23/93) vs 16.1% (205/1274), P=0.001], RSV A [28.3% (41/145) vs 15.3% (187/1222), P=0.001], RSV B [31.3% (10/32) vs 16.3% (218/1335), P=0.042], rhinovirus A/B [22.6% (57/252) vs 15.3% (171/1115), P=0.010]. Conclusion: The study revealed that pneumococcal isolation from NP aspirates is related with respiratory virus detection. The result of this study could be used to investigate how respiratory viruses and pneumococcus cause clinical diseases.

• Clinical and Experimental Pediatrics
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• v.51 no.7
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• pp.729-735
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• 2008

Purpose : Chlamydia trachomatis is one of the most common sexually transmitted diseases and is also a cause of pneumonia in infants. Respiratory infections by respiratory viruses are also common for infants. The objectives of this study were to identify the clinical manifestations and to determine the prevalence of C. trachomatis respiratory infections and coinfections by respiratory viruses in infants younger than 6 months of age. Methods : For this study, we enrolled 6 months or younger infants who were admitted to the Dankook University Hospital between January 2002 and July 2007, with respiratory symptoms. Nasopharyngeal aspirates or throat swabs were collected within s d of hospitalization and C. trachomatis was detected using polymerase chain reaction (PCR). Patients who tested positive underwent multiplex PCR for respiratory viruses. Results : A total of 690 patients underwent chlamydial PCR testing and 36 (5.2%) had positive results. Of the 36, 28 (78%) were male; 30 were vaginally delivered. From the 36 patients positive for C. trachomatis, 26 underwent multiplex respiratory viral PCR; 12 were coinfected with viruses. Respiratory syncytial virus (RSV) was the most frequent pathogen that was detected in 6 patients. Increased C-reactive protein and fever were significant in patients coinfected with respiratory viruses. Conclusion : C. trachomatis can infected in infants delivered by cesarean section as well as in 6 months old or younger infants. Infant with C. trachomatis respiratory infections can also be coinfected with respiratory infection also coinfected with respiratory viruses. Further studies are needed to better understand the prevalence rates of the this infection and its coinfection rate with respiratory viruses.

• Clinical and Experimental Pediatrics
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• v.50 no.2
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• pp.151-156
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• 2007

Purpose : Streptococcus pneumoniae is a major etiologic agent for pneumonia, meningitis, otitis media, and sepsis among young children. Multi-drug resistant strains have raised great concern worldwide, thus the importance of prevention with vaccines has been emphasized. However, vaccines may force the appearance of pneumococcal infections by nonvaccine serotypes. Thus, distribution of pneumococcal serotypes should be monitored to estimate vaccine efficacy. We used a new and efficient multibead assay in determining pnemococcal serotypes. Methods : From January to February 2005, 643 children were recruited from ten day care centers to isolate pneumococci from their oropharynx. Pneumococcal serotyping was performed on 62 pneumococcal isolates from 60 children by multibead assay. This immunoassay required two sets of latex particles coated with pneumococcal polysaccharides and serotype-specific antibodies. Twenty four newly developed monoclonal antibodies specific for common serotypes and a pool of polyclonal rabbit sera for some of the less common serotypes were used. Results : The most prevalent pneumococcal serotypes were serotype 6A, 19A, 19F, 23F, and 11A/D/F which accounted more than 50 precent of all the 62 pneumococcal isolates. We found that multibead assay can be performed very rapidly and objectively. Conclusion : This multibead immunoassay was very useful in serotyping clinical isolates of S. pneumoniae because it was simple, reliable and fast.

• Journal of Food Hygiene and Safety
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• v.15 no.4
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• pp.315-323
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• 2000

Serious consequences can arise from lack of hygiene in mass catering. Microbiological testing is of value in determining hazards for developing a HACCP plan, and in demonstrating to food handlers the reality of the microbial risk. This studies was performed to describe the overall hygiene of cooking utensils and equipments, employees, and environment in mass catering establishments. Generally, hygienic conditions of cutting board and sanitized dish cloth were better than those of other cooking utensils such as knife, sieve, and peeler. It was found that the cross-contamination of knife might be caused by the use of contaminated sanitizing solution. It was observed that there was considerable variation (10$^1$~10$^{5}$ CFU) of the number of general bacteria for employee's hands. The number of general bacteria were influenced from establishment, employee, and the period of analysis. The number of Coliform group for employee's hands was in the range of 10$^2$~10$^4$CFU only at the first analysis. Total aerial bacteria in working area of mass catering establishments was below 7 CFU/Plate and aerial Staphylococcus sp. was not detected at all except one spot.