• Food Science of Animal Resources
• /
• v.33 no.5
• /
• pp.610-616
• /
• 2013

Loop-mediated isothermal amplification (LAMP) is an emerging detection technology for the amplification of DNA under isothermal conditions. The aim of this study was to develop a rapid and reliable LAMP technique for the detection of Cronobacter sakazakii in milk powder. In order to enhance the sensitivity and specificity, LAMP primers targeting outer membrane protein A (ompA) gene of C. sakazakii were designed using Explorer V4 software. Thirty seven C. sakazakii strains and 13 pathogenic microorganisms were used for comparative detection of C. sakazakii using polymerase chain reaction (PCR), real-time PCR, and LAMP. LAMP developed in this study could specifically detect C. sakazakii strains without cross-reactivity with other foodborne pathogens. LAMP products amplified from ompA gene of C. sakazakii were digested with with HhaI and NruI enzyme. The specificity of LAMP was confirmed by restriction fragment length polymorphism (RFLP) analysis. LAMP could detect C. sakazakii within 1 h without bacterial culture and its detection limit was as low as 1 CFU/mL C. sakazakii in milk. In the comparison of the sensitivity, LAMP showed 10,000- and 100-times higher detection limit than PCR or real-time PCR, respectively. Therefore, this study can conclude that LAMP is a rapid and reliable detection technique for C. sakazakii contaminated in powdered milk.

• Journal of IKEEE
• /
• v.23 no.1
• /
• pp.295-301
• /
• 2019

A heater in a portable real-time polymerase chain reaction(PCR) system is one of the important factors for controlling the PCR thermocycle precisely. Since heaters are integrated on a small-sized PCR chip for rapid heating and fabricated by semiconductor processes, the cost of producing PCR chips is high. Here, we propose to use chip resistors as an inexpensive and accurate temperature control method. The temperature distribution was simulated using one or two chip resistors on a real-time PCR chip and the PCR chip with uniform temperature distribution was fabricated. The temperature rise and fall rates were $18^{\circ}C/s$ and $3^{\circ}C/s$, respectively.

• Journal of Veterinary Clinics
• /
• v.22 no.4
• /
• pp.348-352
• /
• 2005

We described a rapid, sensitive and reproducible real-time PCR assay for detection and quantitation of canine parvovirus type 2 in the feces of dogs with parvovirus infection. The method was demonstrated to be highly specific and sensitive, allowing a precise canine parvovirus type-2 quantitation over range of eight orders of magnitude from $10^2\;to\;10^9$ copies of standard DNA. Then, fecal samples from parvovirus infected dogs were analyzed by conventional PCR and real-time PCR. Real-time PCR is more sensitive than conventional PCR, allowing to detect low viral titers of CPV-2 in infected dogs. By real-time PCR, a wide range of parvovirus particles was found in the samples from $1.45\times10^6\;to\;9.45\times10^8$ copies/0.01g of feces. However, when dogs are in infection of parvovirus, it is difficult to prove that the numbers of peripheral blood leukocytes are correlated with those of fecal shedding virus.

• Journal of Korean society of Dental Hygiene
• /
• v.21 no.5
• /
• pp.555-565
• /
• 2021

Objectives: This study was conducted to analyze peri-implantitis bacteria and identify their associations with health status and health activities. Methods: Gingival sulcus fluid at the implant's periodontal pockets sampled from the participants were analyzed by multiplex real time PCR. Results: Participants had strains in the order of 100% F. nucleatum, 98.0% E. corrodens, and 96.0% P. micra, and the correlation between C. rectus and E. nodatum was high (p<0.01). Diabetic group (P. gingivalis, P. nigrescens) hypertension (P. nigrescens), group with four or more periodontal pockets (P. gingivalis, T. dentica, P. intermedia, E. nodatum, and C. rectum), smoking (P. micra, E. corrodens), drinking (T. dentola), and scaling groups (C. rectus) were found to have more strains (p<0.05). Conclusions: Representative pathogenic microorganisms detected in periodontal pockets of implants were similar to dental periodontal pockets; however there were differences in the amount and distribution of microorganisms, and they were affected by health status and health behavior.

• Journal of Korean society of Dental Hygiene
• /
• v.24 no.2
• /
• pp.131-139
• /
• 2024

Objectives: Oral bacterial samples included subgingival, supragingival, and saliva plaques. As the diversity and number of microorganisms deffer depending on the area of the oral cavity and the method used, an appropriate and reliable collection method is important. The present study investigated oral bacterial sampling methods. Methods: Supragingival dental plaque was collected from the buccal and lingual tooth surfaces of study participants using sterilized cotton swabs. Plaques were collected from the subgingival area using a sterilized curette. Bacterial genomic DNA was extracted using MagNA Pure 96 DNA and Viral NA low-volume kits. Real-time polymerase chain reaction (PCR) was performed using the PowerCheck^TM Periodontitis Pathogens Multiplex Real-time PCR kit. Results: Aggregatibacter actinomycetemcomitans, Prevotella intermedia, and Fusobacterium nucleatum of the orange complex were not observed in the subgingival biofilms of all study participants. For Porphyromonas. gingivalis, a significant correlation was observed between supragingival, subgingival, and total tooth surface biofilms. Compared to the supragingival and subgingival biofilmss, total tooth surface biofilm exhibited the highest bacterial count when the inswabbing method was used. Conclusions: Based on these findings, the supragingival swab method is recommended for oral bacterial research.

• Korean Journal of Food Science and Technology
• /
• v.36 no.5
• /
• pp.723-727
• /
• 2004

Qualitative and quantitative PCR methods were performed to examine detection and quantitation of epsps inserted into genetically modified soybean (GMS) in processed foods, soy milk, tofu, and biji (soybean curd residue). Using PCR amplification to produce two (121 and 330 bp) epsps in GMS, detection limits of GMS in soy milk, tofu, and biji containing 0.01% GMS were measured. For quantitative detection, test samples containing 1, 3, and 5% GMS were measured by real-time PCR method. Results show real-time PCR method is applicable to detect GMS quantitatively in processed foods.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.11 no.6
• /
• pp.2093-2098
• /
• 2010

Insulin resistance plays a central role in fatty liver, a part of the metabolic syndrome. This study examined the relationship between fatty liver, metabolic abnormalities and mitochondrial DNA [mtDNA] copy number in peripheral blood that is correlated with diabetes or metabolic markers. Fatty liver was assessed by questionnaire on alcohol consumption and abdominal ultrasonography. MtDNA copy number in peripheral leukocytes was measured by a real-time quantitative polymerase chain reaction [PCR]. Among 445 subjects, 148 subjects had hepatic steatosis and 297 were controls. mtDNA copy number was significantly lower in fatty liver group in comparison with that of normal finding group. This result is similar in both groups, alcoholic or non-alcoholic fatty liver group. MtDNA copy number was inversely correlated with alanine aminotransferase [ALT], aspartate aminotransferase [AST], gamma-glutamyltransferase [$\gamma$-GTP], body mass index [BMI], waist circumference, diastolic blood pressure, and free fatty acid. MtDNA copy number in peripheral leukocytes was associated with fatty liver and insulin resistance related factors.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.23 no.1
• /
• pp.35-39
• /
• 2019

Purpose Hepatitis B virus (hepatitis B virus, HBV) infection is a worldwide major public health problem and it is known as a major cause of chronic hepatitis, liver cirrhosis and liver cancer. And serologic tests of hepatitis B virus is essential for diagnosing and treating these diseases. In addition, with the development of molecular diagnostics, the detection of HBV DNA in serum diagnoses HBV infection and is recognized as an important indicator for the antiviral agent treatment response assessment. We performed HBeAg assay using Immunoradiometric assay (IRMA) and Chemiluminescent Microparticle Immunoassay (CMIA) in hepatitis B patients treated with antiviral agents. The detection rate of HBV DNA in serum was measured and compared by RT-PCR (Real Time - Polymerase Chain Reaction) method Materials and Methods HBeAg serum examination and HBV DNA quantification test were conducted on 270 hepatitis B patients undergoing anti-virus treatment after diagnosis of hepatitis B virus infection. Two serologic tests (IRMA, CMIA) with different detection principles were applied for the HBeAg serum test. Serum HBV DNA was quantitatively measured by real-time polymerase chain reaction (RT-PCR) using the Abbott m2000 System. Results The detection rate of HBeAg was 24.1% (65/270) for IRMA and 82.2% (222/270) for CMIA. Detection rate of serum HBV DNA by real-time RT-PCR is 29.3% (79/270). The measured amount of serum HBV DNA concentration is $4.8{\times}10^7{\pm}1.9{\times}10^8IU/mL$($mean{\pm}SD$). The minimum value is 16IU/mL, the maximum value is $1.0{\times}10^9IU/mL$, and the reference value for quantitative detection limit is 15IU/mL. The detection rates and concentrations of HBV DNA by group according to the results of HBeAg serological (IRMA, CMIA)tests were as follows. 1) Group I (IRMA negative, CMIA positive, N = 169), HBV DNA detection rate of 17.7% (30/169), $6.8{\times}10^5{\pm}1.9{\times}10^6IU/mL$ 2) Group II (IRMA positive, CMIA positive, N = 53), HBV DNA detection rate 62.3% (33/53), $1.1{\times}10^8{\pm}2.8{\times}10^8IU/mL$ 3) Group III (IRMA negative, CMIA negative, N = 36), HBV DNA detection rate 36.1% (13/36), $3.0{\times}10^5{\pm}1.1{\times}10^6IU/mL$ 4) Group IV(IRMA positive, CMIA negative, N = 12), HBV DNA detection rate 25% (3/12), $1.3{\times}10^3{\pm}1.1{\times}10^3IU/mL$ Conclusion HBeAg detection rate according to the serological test showed a large difference. This difference is considered for a number of reasons such as characteristics of the Ab used for assay kit and epitope, HBV of genotype. Detection rate and the concentration of the group-specific HBV DNA classified serologic results confirmed the high detection rate and the concentration in Group II (IRMA-positive, CMIA positive, N = 53).

• 보존과학연구
• /
• s.32
• /
• pp.171-183
• /
• 2011

In this study molecular genetic analysis was carried out on 4 human skeletal remains from Osuri, Buyeo. We showed that real-time PCR is the method of the choice to assess the initial number of genuine ancient DNA molecules. Human mitochondrial DNA quantification was accomplished by the real-time PCR for the cytochrome b gene of the mitochondria. Histological results proved to be a good potentiality for biochemical analysis using biomolecule. The level of specimen's preservation state was proved that level of quantitative result was BO-04, BO-01, BO-03, BO-02. Continually, we showed that biochemical and biomolecule results for the level of preservation state were similar. This study will be useful to important material for predicting biochemistry and biology analysis of the ancient bone.

• Neonatal Medicine
• /
• v.16 no.2
• /
• pp.221-233
• /
• 2009

Purpose: Erythropoietin (EPO) has neuroprotective effects in many animal models of brain injury, including hypoxic-ischemic (HI) encephalopathy, trauma, and excitotoxicity. Current studies have demonstrated the neuroprotective effects of EPO, but limited data are available for the neonatal periods. Here in we investigated whether recombinant human EPO (rHuEPO) can protect the developing rat brain from HI injury via modulation of NMDA receptors. Methods: In an in vitro model, embryonic cortical neuronal cell cultures from Sprague-Dawley (SD) rats at 19-days gestation were established. The cultured cells were divided into five groups: normoxia (N), hypoxia (H), and 1, 10, and 100 IU/mL rHuEPO-treated (H+E1, H+ E10, and H+E100) groups. To estimate cell viability and growth, a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay was done. In an in vivo model, left carotid artery ligation was performed on 7-day-old SD rat pups. The animals were divided into six groups; normoxia control (NC), normoxia Sham-operated (NS), hypoxia-ischemia only (H), hypoxia-ischemia+vehicle (HV), hypoxia-ischemia+rHuEPO before a HI injury (HE-B), and hypoxia-ischemia+rHuEPO after a HI injury (HE-A). The morphologic changes following brain injuries were noted using hematoxylin and eosin (H/E) staining. Real-time PCR using primers of subunits of NMDA receptors (NR1, NR2A, NR2B, NR2C and NR2D) mRNA were performed. Results: Cell viability in the H group was decreased to less than 60% of that in the N group. In the H+E1 and H+E10 groups, cell viability was increased to >80% of the N group, but cell viability in the H+E100 group did not recover. The percentage of the left hemisphere area compared the to the right hemisphere area were 98.9% in the NC group, 99.1% in the NS group, 57.1% in the H group, 57.0% in the HV group, 87.6% in the HE-B group, and 91.6% in the HE-A group. Real-time PCR analysis of the expressions of subunits of NMDA receptors mRNAs in the in vitro and in vivo neonatal HI brain injuries generally revealed that the expression in the H group was decreased compared to the N group and the expressions in the rHuEPO-treated groups was increased compared to the H group. Conclusion: rHuEPO has neuroprotective property in perinatal HI brain injury via modulation of N-methyl-D-aspartate receptors.