• Food Science and Biotechnology
• /
• v.17 no.3
• /
• pp.651-654
• /
• 2008

In order to enhance the efficacy of norovirus detection by reverse transcriptase-polymerase chain reaction (RT-PCR) and nested PCR, this study developed a norovirus mRNA concentration method using poly oligo dT-conjugated magnetic beads. An efficient norovirus detection protocol was performed on commercial ham using 2 viral elution buffers (glycine buffer and Tris beef extract buffer) and 2 concentration solutions [polyethylene glycol (PEG) and zirconium hydroxide]. The different approaches were verified by RT-PCR and nested PCR. This method was performed on ham in less than 8 hr by artificial inoculation of serial dilutions of the virus ranging from 1,000 to 1 RT-PCR unit/mL. The viral extraction and concentration method had 10-fold higher sensitivity using the combination of Tris beef extract buffer and PEG as compared to glycine buffer and zirconium hydroxide. This method proved that RT-PCR and nested PCR have the sensitive ability to detect norovirus in commercial ham, in that norovirus was successfully detected in artificially contaminated samples at a detection level as low as 1-10 RT-PCR unit/mL. Overall, such a detection limit suggests this protocol is both quick and efficient in terms of its potential use for detecting norovirus in meat products.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.32 no.4
• /
• pp.371-377
• /
• 2008

Our precedent study has reported glass-PDMS (polydimethylsiloxane) based biochip for the gene PCR (polymerase chain reaction). To prevent the contamination of bio sample, the once used biochip must not be used repeatedly. However, the fabrication cost of microheater and microsensor of the biochip was not cheap to use it as a disposable chip. This paper proposes new PCR-chip where the glass substrate integrated with the microheater and microsensor is detachable from the reaction chamber where the sample is injected. That makes it possible to reuse the glass substrate repeatedly. The performance of the proposed detachable PCR-chip was compared with that of the precedent monolithic PCR-chip. The results showed that the SRY (sex determining Y chromosome) gene PCR was successfully performed in the detachable chip compared with the monolithic chip. However, the more efforts to improve the efficiency of surface treatment of PDMS chip are needed to increase the possibility of applying the detachable chip to the detecting of male infertility.

• Food Science and Biotechnology
• /
• v.17 no.3
• /
• pp.569-572
• /
• 2008

A multiplex polymerase chain reaction (PCR) method was developed to simultaneously detect 3 events of genetically modified (GM) maize. The event-specific primers were used to discriminate the following 3 events of GM maize (DAS-59122-7, TC6275, and MIR604) using multiplex PCR method. The zein gene was used as an endogenous maize reference gene in the multiplex PCR detection. The primer pair Zein-FIR producing a 99 bp amplicon was used to amplify the zein gene. The primer JI-Das-F1/R1 for DAS-59122-7, JI-TC6275-F3/R3 for TC6275, and JI-MIR F1/R1 for MIR604 yielded an amplicon of 130, 162, and 197 bp, respectively. The detection limit of multiplex PCR was 1% for DAS-59122-7, TC6275, and MIR604 for one reaction.

• Korean Journal of Veterinary Research
• /
• v.38 no.3
• /
• pp.565-573
• /
• 1998

To study the specific tools for the diagnosis of Newcastle disease virus (NDV) in chicken, polymerase chain reaction (PCR) and its presumable conditions were evaluated for the detection of hemagglutinin-neuraminidase (HN) gene of NDV RNA. For these purposes, Kyojeongwon strain of the NDV was propagated in allantoic cavity of SPF embryonating chicken eggs, and viral RNA was extracted from fractionated virus after the allantoic fluids were ultracentrifuged with sucrose gradient. The first-strand cDNA was then made for the HN gene of NDV RNA by reverse transcription at $42^{\circ}C$ for 1 hour using specific primer complementary to the HN gene. The single-stranded cDNA was used as template in the PCR of the HN-DNA, and various conditions of the PCR were evaluated to set up method for the specific detection of the HN-DNA. The PCR conditions promising for the detection of HN gene consist of preheating at $94^{\circ}C$, 5 min, 30 cycles of denaturation at $94^{\circ}C$, 1 min, annealing at $55^{\circ}C$, 1 min and polymerization at $72^{\circ}C$, 2 min, and a cycle of extension at $72^{\circ}C$, 5 min. when NDVs of allantoic fluids without fractionation were applied to the above PCR condition, the HN genes were detected effectively not only from Kyojeongwon but from other velogenic strains such as Herts and a field isolate.

• Korean Journal of Microbiology
• /
• v.38 no.4
• /
• pp.306-311
• /
• 2002

PCR of the mecA gene for the rapid detection of methicillin-resistant staphylococci was perfomed and compared with the antibiotic sensitivity test. A total of 43 strains of staphylococi from clinical specimens were used in this study. An antibiotic sensitivity test by the agar dilution method of NCCLS (The National Commitee for Clinical Laboratory Standard) was performed for the strains. Among them, 39 isolates were methicillin-resistant (MRS), and 4 isolates were methicillin-susceptible (MSS). With the exception for one strain (Staphylococcus cohnii, HRC2-4), all MRS strains amplified the expected 533 bp fragments of the mecA gene by PCR, However, one strain (Staphylococcus aureus, HSA1-10) that was classified as a sensitive strain by the antibiotic sensitivity test was mecA positive by PCR. All 35 methicillin-resistant Staphylococcus aureus (MRSA) strains were mecA positive, but overall, concordance between the results of the mecA PCR and antibiotic sensitivity test was 95.6%.

• Journal of Veterinary Clinics
• /
• v.27 no.1
• /
• pp.23-28
• /
• 2010

Mycobacterium avium ssp paratuberculosis, intracellular bacteria that can cause chronic granulomatous enteritis in cattle, continues to pose significant economic losses and health problem with high prevalence. The purpose of this study is the polymerase chain reaction (PCR)-base strategy for early detection of M. avium ssp paratuberculosis in whole blood. Blood samples were collected from korean cattles in Jeonbuk, Korea. The 16 out of 88 serum samples were detected M. partuberculosis by ELISA. Then samples of infected 8 Korean cattles were amplified by PCR. The PCR amplified targets are 16s rDNA and heat shock protein 65kDa (hsp 65). The 16s rDNA provided a highly sensitive and specific tool for the direct detection of mycobacteria. In addition M. avium was confirmed characteristically by the hsp65. Finally there were sure to M. avium ssp paratuberculosis by IS900 PCR. The restriction fragment length polymorphism was identified by PCR amplifications and subsequence restriction enzyme digestions with Pst I of a hsp65. These results indicate that confirm M. avium with 16s rDNA, hsp65 and a restriction fragment length polymorphism in the hsp65 gene can be seem the other pattern. Therefore, these results can be used for clinical direct detections of M. avium ssp paratuberculosis in whole blood of Korean cattle and also to be used epidemiological researches.

• Preventive Nutrition and Food Science
• /
• v.9 no.3
• /
• pp.276-282
• /
• 2004

Marginal Zn deficiency is prevalent through the world and yet human zinc status has not been properly assessed due to the lack of a reliable diagnostic indicator. One potential possibility for zinc status assessment using Zn-binding protein, metallothionein (MT)-mRNA, has been proposed. The purpose of the present study was aimed to show whether measurement of mononuclear cell (MNC) MT mRNA, using a competitive-reverse transcriptase-polymerase chain reaction (competitive-RT-PCR) assay, could indicate zinc status in human subjects. In this study, MNC MT-mRNA expression was measured using a competitive-RT-PCR to compare before and after 14 days of zinc supplementation (50 mg Zn/das zinc gluconate). RT-PCR oligonucleotide primers which were designed to amplify both a 278 bp segment of the human MT-2A cDNA and a 198 bp mutant competitor cDNA template from MNCs, were prepared. MT-2A mRNA was normalized by reference to the housekeeping gene, $\beta$-actin, mRNA for which was also measured by competitive-RT-PCR. There was considerable inter-individual variation in MT-mRNA concentration and yet, the mean MT-2A mRNA level increased 4.7-fold after Zn supplementation, as compared to before Zn supplementation. This MT-2A mRNA level was shown as the same pattern and, even more sensitive assay, compared to the conventional plasma and red blood cells (RBCs) Zn assessment in which plasma and RBCs zinc levels increased 2.3- and 1.2-fold, respectively (p<0.05). We suggest that MT competitive-RT-PCR can be a useful assessment tool for evaluating human zinc status.

• 한국생물공학회:학술대회논문집
• /
• 2000.04a
• /
• pp.592-595
• /
• 2000

In human chromosome, a short sequence of DNA has been repeated a number of times. These repeats are called variable number of tandem repeat(VNTR) or short tandem repeat(STR) which has short repeat core. VNTR and STR are used in the field of forensic science, evolution, and anthropology. In this work, we examined allele frequencies of 3 VNTR(YNZ22, NeuR, D21S11) and one STR(Humth01) in a Korean population sample by polymerase chain reaction(PCR) followed by high-resolution polyacrylamide gelelectrophoresis(PAGE) with silver staining. Subsequently, the polymorphism information content(PIC) was calculated : the highest PIC was observed for the NeuR locus(0.95680) and lowest for the Humth01 locus(0.75809).

• Journal of Microbiology and Biotechnology
• /
• v.4 no.1
• /
• pp.20-23
• /
• 1994

The polymerase chain reaction was used to study the genes inducible under stress from the heavy metal cadmium. Schizosaccharomyces pombe, grown in the presence or absence of sublethal concentration of cadmium, was isolated to purify the total RNAs. The Induced RNA Random Fishing (IRRF) method in which random oligonucleotides were used as primers was applied to the identification of cadmium-induced gene expressions. A PCR-DNA product of 400-bp was cloned and sequenced. Computer analysis showed that this DNA has no homology with any known DNA sequences in GenBank or EMBL databases. The induction of this gene was confirmed by Northern blot analysis of total RNAs isolated from both cadmium-treated and untreated yeast cells.

• Parasites, Hosts and Diseases
• /
• v.41 no.2
• /
• pp.125-127
• /
• 2003

Muscle larvae of Trichinella isolates from two outbreaks in Korea were analyzed by a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and multiple-PCR. All of the muscle larvae showed a band similar to that of T. spiralis larvae of the reference strain. The two Korean Trichinella isolates (isolate code ISS623 and ISS1078) might be classifiable to Trichinella spiralis.