• Journal of Life Science
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• v.15 no.3 s.70
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• pp.505-512
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• 2005

Excitotoxicity and epileptogenesis have often been associated with glutamate receptor activation. Accumulating evidences indicates that topiramate (TPM), an antiepileptic drug with multiple mechanisms of action has neuroprotective activity. We explored the neuroprotective effect of TPM on the status epilepticus (SE)-induced hippocampal neuronal death. After development of SE by kainite injection (15 mg/Kg), rats were treated with TPM (10mg/kg) for 1 week. The neuronal death was detected by Apop tag in situ detection kit, and the expression levels of glutamate receptors were semi-quantitatively analyzed by immunoblot. Kainate-induced SE caused a significant neuronal death and cell loss in CAI and CA3 regions of hippocampus at 1 week. However, treatment of TPM for 1 week after SE markedly reduced hippocampal neuronal death. The expression of N-methyl-D-aspartate (NMDA) receptor subunit 1, was increased by SE, but was not affected by 1 week treatment of TPM. The expressions of NMDA receptor subunit 2a and 2b were not changed by either SE or TPM. As for ${\alpha}-amino-3-hydroxy-5-methyl-4-isoxazole-propionate$ (AMPA) glutamate receptors (GluR), kainate-induced SE markedly up-regulated GluR1 expression but down-regulated GluR2 expression, leading to increased formation of $Ca^{2+}$ permeable GluR2- lacking AMPA receptors. TPM administration for 1 week attenuated SE-induced expression of both the up-regulation of GluR1 and down-regulation of GluR2, reversing the ratio of GluR1/GluR2 to the control value. In conclusion, TPM protects neuronal cell death against glutamate induced excitotoxicity in kainate-induced SE model, supporting the potential of TPM as a neuroprotective agent.

• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.176-182
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• 2006

Sensitive and specific monoclonal antibody (MAb) was produced from hybridoma (1H11-5) obtained by fusion of myeloma cell (V653) and spleen cell isolated from mouse immunized sulfamthazine (SMZ)-HG-KLH. Direct competitive ELISA was developed for rapid detection of SMZ in milk samples using MAb against SMZ with optimized conditions between MAb and SMZ-HG-HRP conjugate, and applicable conditions for analysis of milk samples were established. Detection range of immunoassay was 0.1 to 100 ppb. Recoveries from spiked raw milk and processed milk samples averaged 82.1-120.7 and 82.1-97.1%, respectively.

• Korean Journal of Clinical Laboratory Science
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• v.51 no.2
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• pp.171-176
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• 2019

A comparative study between commercially available mycobacteria growth indicator tubes (MGIT) in the BACTEC MGIT 960 System and the conventional Ogawa media was carried out to assess the effectiveness of the re-decontaminating process for the recovery of mycobacteria. Processed specimens with 5% sodium hydroxide and 0.5% N-acetyl-L-cysteine were inoculated into MGIT and Ogawa media. The acid fast bacilli (AFB) recovered from the cultures were identified using a mycobacterium tuberculosis (TB) antigen kit. If contaminants were observed in the MGIT tubes within five days, a decontaminating process was repeated. A total of 1,190 out of 4,790 (24.8%) specimens showed positive results using the BACTEC MGIT 960 system. Among them, 278 specimens were reprocessed. When the MGIT and Ogawa results were compared, it showed discordant results (weighted kappa value: 0.283). One TB and 10 nontuberculous mycobacteria (NTM) were newly detected in MGIT only. The likely benefit of the re-decontaminating process is the detection of additional mycobacteria that could not be detected without a re-decontaminating process despite being small in number. In addition to the combination of MGIT and Ogawa, the re-decontaminating process is recommended in the case of contaminations to recover mycobacteria.

• Journal of Animal Science and Technology
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• v.49 no.5
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• pp.559-568
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• 2007

Recently, copy number variations (CNV) of genes or genomic segments have been intensively studied and various analysis methods have been developed. In this study, quantitative oligonucleotide ligation assay (qOLA) was applied to investigate CNV of KIT gene in the Landrace breed. A combined assay using qOLA and pyrosequencing, 6 genotype classes, I1/I1 or I3/i (IBe), I1/I2 or I3/IP, I1/I3, I1/IP or I2/i (IBe), I2/I2and I2/IP, were identified from 44 Landrace pigs. Genotype assignment using grouping features of measurements on a scatter plot showed 100% agreement with those using a statistical assignment by PROC FASTCLUS procedure implemented in the SAS package. Two versions (3100 and 3130) of ABI sequencers gave the same genotyping results, indicating there was no influence on qOLA by different versions of instrument, however, the means of standard deviation and coefficient of variation from the qOLA on a ABI 3130 (2.33 and 4.10) was lower than those from the qOLA on a ABI 3100 (2.67 and 4.81). Effect of proteinase K treatment on the PCR product followed by qOLA was very clear because noise peaks were disappeared and the observed ration fit better to the reference ratio corresponding to each genotype.

• Korean Journal of Food Science and Technology
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• v.43 no.2
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• pp.161-168
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• 2011

The purpose of this study was to evaluate microbiological contamination of fresh vegetables in Korea. Twenty types of vegetables were tested for total aerobic bacteria, coliforms, Escherichia coli, yeast and mold, and pathogenic bacteria such as Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, Salmonella, E. coli O157:H7, Cronobacter sakazakii, Shigella, and Campylobacter. Levels of total aerobic bacteria and coliform on 20 vegetables were between 3.74 and 8.04 log CFU/g, and 0.16 and 5.02 log CFU/g, respectively. The highest contamination levels of total aerobic bacteria were observed on water dropwort, sprouts, mungbean sprout, and ballflower root. There was no significant difference (p>0.05) in microbial contamination levels of total aerobic count, coliform, E. coli, yeast and mold between organic and nonorganic vegetables. When isolation methods using selective agars were applied, L. monocytogenes, B. cereus, Salmonella and Campylobacter were isolated from some fresh vegetable samples. Results of API kit tests showed that L. monocytogenes was identified on Chinese cabbage, cucumber, soybean sprouts, and iceberg lettuce while Salmonella was identified on Korean leek. Furthermore, Campylobacter jejuni was also identified in more than 50 of the 100 samples. However, when positive samples from API kit were tested for real-time PCR or 16S rRNA sequencing method, only B. cereus from perilla leaf, carrot, water dropwort, and sprouts showed positive results. These results indicate that selective agar and API kit detection methods might result in false positive results for some pathogens. Therefore, studies need to improve isolation or confirmation methods for such pathogens.

• Korean Journal of Microbiology
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• v.44 no.4
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• pp.293-298
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• 2008

HCV is transmitted via various plasma derived products. Current methods to detect hepatitis C virus (HCV) are based on its antibody detection in the donated blood and plasma. Viral contamination can potentially escape such detection during the window period of infection, when no antibody is present or the level of antibody is too low to detect. It is trying to application of nucleic acid amplification tests (NAT) for the direct detection of HCV. The objective of this study was to develop a reliable NAT for the HCV RNA detection from plasma-derived products. The most useful primers was selected for NAT among 5 sets of primers. We have also found that QIAamp viral RNA isolation kit was the most efficient for HCV RNA isolation. The highest sensitivity and specificity was appeared in $48^{\circ}C$ annealing temperature and 30 pmol of primers. With a spiking of HCV to albumin, immunoglobulins and coagulation factors, NAT can detect up to 100 IU/ml. Meanwhile, COBAS amplicor HCV 2.0 afforded a lower sensitivity in high concentrated intramuscular immunoglobulins to below 500 IU/ml. Our results suggested that NAT appears to be a highly sensitive and specific method for HCV RNA detection in plasma-derived products.

• Korean Journal of Microbiology
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• v.41 no.3
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• pp.168-176
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• 2005

Vibrio vulnificus, one of the marine bacterial pathogens causing septicemia, was detected using molecular methods, namely, PCR and/or Southern hybridization, and real-time PCR. Extracted and purified total DNAs by using commercial kits were used as templates for PCR. Multiplex-PCR was conducted by employing three sets of primers for the genes, hemolysin (vvhA), phosphomannomutase (pmm), and metalloprotease (vvpE), for V vulnificus virulence. The presence of DMSO ($5\%$) and BSA ($0.1\%$) in PCR reaction mixture improved a detection efficiency by higher PCR band intensities. TaqMan real-time PCR was carried out by using gene segment of vvhA as a target. Detection limit of PCR/Southern hybridization without enrichments was to be around $10^2\;cells\;g^{-1}$ of sample. However, those three methods using the enrichment at $35^{\circ}C$ in APW showed high sensitivity ($2\~10\;cells\;g^{-1}$ of sediments). Highly sensitive detection of V vulnificus by real-time PCR was achieved within $5\~6$ hr, whereas the detection by PCR/Southern hybridization required about 36 hr. Thus, it was evident that real-time PCR is the most rapid and efficient method for detecting V vulnificus in tidal flat sediments.

• Clinical and Experimental Pediatrics
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• v.52 no.12
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• pp.1358-1363
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• 2009

Purpose:The aim of this study was to determine the prevalence of asymptomatic nasopharyngeal carriages in children using a multiplex reverse transcriptase-polymerase chain reaction (mRT-PCR) assay kit. Methods:We obtained nasopharyngeal swabs from 33 children without any underlying disease from July 25 to July 28, 2008. The children were free from the signs of respiratory tract infections at the time of sampling. DNA was extracted from the swabs and subjected to multiplex RT-PCR using a primer set for the detection of pneumococci ($Seeplex^{(R)}$ PneumoBacter ACE Detection Seegene, Seoul, Korea). The amplified PCR products were separated on 2% agarose gels and stained with either ethidium bromide or screen tape system (Lab901 Scotland, UK). Results:A total of 33 children (male, 15 female, 18) aged between 3.2 and 16.3 (median, 8.2) years were included in this study. The mRT-PCR detected colonized bacteria (Streptococcus pneumoniae, Hemophilus influenzae, Chlamydia pneumoniae, and Bordetella pertussis) in 30 children (90.9%). Of these, 13 children (39.4%) showed more than 2 bacteria: 12 children were positive for 2 bacteria (S. pneumoniae and H. influenzae) and 1 child was positive for 3 bacteria (S. pneumoniae, H. influenzae, and C. pneumoniae). Conclusion:mRT-PCR was found to be a sensitive tool for the detection of asymptomatic nasopharyngeal carriages. Clinical significances of the bacteria detected by mRT-PCR will have to be evaluated in the future.

• Journal of Food Hygiene and Safety
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• v.30 no.2
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• pp.150-158
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• 2015

This article reports the development of an effective test procedure for detection of norovirus (NoV) in foods of diverse matrices. In this study, target foods included fermented milk, soybean paste, powders made from uncooked grains and vegetables, sesame leaves preserved in soy sauce, pickled mooli, and mooli. Viral recovery varied depending on the food matrices or elution buffers tested. Buffers were compared to determine effective elution buffers from artificially virus-contaminated foods. The conventional test procedure for concentrating viruses from food (elution-polyethylene glycol(PEG) precipitation-chloroform-PEG precipitation) was modified to save time by eliminating one PEG precipitation step. The modified procedure (elution-chloroform-PEG precipitation) was able to concentrate viruses more effectively than the conventional procedure. It also removed RT-PCR inhibitors effectively. The modified procedure was applied to target food for genogroup II NoV detection. NoV RNA was detected at the initial inoculum levels 3.125-12.5 RT-PCR units per 10-25 g tested food. The use of this newly established procedure should facilitate detection of low levels of norovirus in diverse foods.

• Journal of Food Hygiene and Safety
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• v.28 no.3
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• pp.213-216
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• 2013

Antibiotic Detection Kit (Combination I), a lateral flow immunoassay (LFIA) developed for the detection of antibiotic residues in milk, was utilized for the analysis of antibiotic residues in the muscle tissue of olive flounder. After 60-min treatment by dipping in water dosed with ampicillin (200-g/ton water), the residue depletion of ampicillin was investigated in 25 cultured olive flounder (Paralichthys olivaceus). Muscles of fish were sampled on the 1st, 2nd, 3rd, 4th and 5th day after drug treatment. The concentration of ampicillin in the muscle was determined by LFIA. The absorbance ratio of the sample to the control blank (Bs/Bo) was employed as an index to determine the muscle residues in olive flounder. To investigate the recovery rate, standard solutions were added to muscle samples to give final concentrations in the muscle of 4 and 8 ng/ml. The recovery rates of all spiked samples were > 96% of the spiked value. Ampicillin was detected in the muscle of fish treated with the drug until the 2nd day of the withdrawal period. The present study showed that the LFIA can be easily adopted to predict ampicillin residues in tissue of farmed fishes.